diff --git a/application/config/navigation.php b/application/config/navigation.php
index 5f3414759..092c00cc5 100644
--- a/application/config/navigation.php
+++ b/application/config/navigation.php
@@ -120,11 +120,18 @@ $config['navigation_header'] = array(
 					'sort' => 30,
 					'requiredPermissions' => 'system/issues_verwalten:r'
 				),
+				'plausichecks' => array(
+					'link' => site_url('system/issues/Plausichecks'),
+					'description' => 'Plausichecks',
+					'expand' => true,
+					'sort' => 40,
+					'requiredPermissions' => 'system/issues_verwalten:r'
+				),
 				'gruppenmanagement' => array(
 					'link' => site_url('person/Gruppenmanagement'),
 					'description' => 'Gruppenmanagement',
 					'expand' => true,
-					'sort' => 40,
+					'sort' => 50,
 					'requiredPermissions' => 'lehre/gruppenmanager:r'
 				)
 			)
diff --git a/application/controllers/jobs/IssueResolver.php b/application/controllers/jobs/IssueResolver.php
index 17c4cb9ce..78e867936 100755
--- a/application/controllers/jobs/IssueResolver.php
+++ b/application/controllers/jobs/IssueResolver.php
@@ -22,7 +22,32 @@ class IssueResolver extends IssueResolver_Controller
 			'CORE_INOUT_0003' => 'CORE_INOUT_0003',
 			'CORE_INOUT_0004' => 'CORE_INOUT_0004',
 			'CORE_INOUT_0005' => 'CORE_INOUT_0005',
-			'CORE_INOUT_0006' => 'CORE_INOUT_0006'
+			'CORE_INOUT_0006' => 'CORE_INOUT_0006',
+			'CORE_INOUT_0007' => 'CORE_INOUT_0007',
+			'CORE_INOUT_0008' => 'CORE_INOUT_0008',
+			'CORE_INOUT_0009' => 'CORE_INOUT_0009',
+			'CORE_STG_0001' => 'CORE_STG_0001',
+			'CORE_STG_0002' => 'CORE_STG_0002',
+			'CORE_STG_0003' => 'CORE_STG_0003',
+			'CORE_STG_0004' => 'CORE_STG_0004',
+			'CORE_STUDENTSTATUS_0001' => 'CORE_STUDENTSTATUS_0001',
+			'CORE_STUDENTSTATUS_0002' => 'CORE_STUDENTSTATUS_0002',
+			'CORE_STUDENTSTATUS_0003' => 'CORE_STUDENTSTATUS_0003',
+			'CORE_STUDENTSTATUS_0004' => 'CORE_STUDENTSTATUS_0004',
+			'CORE_STUDENTSTATUS_0005' => 'CORE_STUDENTSTATUS_0005',
+			'CORE_STUDENTSTATUS_0006' => 'CORE_STUDENTSTATUS_0006',
+			'CORE_STUDENTSTATUS_0007' => 'CORE_STUDENTSTATUS_0007',
+			'CORE_STUDENTSTATUS_0008' => 'CORE_STUDENTSTATUS_0008',
+			'CORE_STUDENTSTATUS_0009' => 'CORE_STUDENTSTATUS_0009',
+			'CORE_STUDENTSTATUS_0010' => 'CORE_STUDENTSTATUS_0010',
+			'CORE_STUDENTSTATUS_0011' => 'CORE_STUDENTSTATUS_0011',
+			'CORE_STUDENTSTATUS_0012' => 'CORE_STUDENTSTATUS_0012',
+			'CORE_STUDENTSTATUS_0013' => 'CORE_STUDENTSTATUS_0013',
+			'CORE_STUDENTSTATUS_0014' => 'CORE_STUDENTSTATUS_0014',
+			'CORE_PERSON_0001' => 'CORE_PERSON_0001',
+			'CORE_PERSON_0002' => 'CORE_PERSON_0002',
+			'CORE_PERSON_0003' => 'CORE_PERSON_0003',
+			'CORE_PERSON_0004' => 'CORE_PERSON_0004'
 		);
 	}
 }
diff --git a/application/controllers/jobs/PlausiIssueProducer.php b/application/controllers/jobs/PlausiIssueProducer.php
new file mode 100644
index 000000000..943d7aa46
--- /dev/null
+++ b/application/controllers/jobs/PlausiIssueProducer.php
@@ -0,0 +1,62 @@
+<?php
+
+/**
+ * Job for producing Plausicheck issues
+ */
+class PlausiIssueProducer extends JOB_Controller
+{
+	public function __construct()
+	{
+		parent::__construct();
+
+		$this->load->library('issues/PlausicheckProducerLib');
+		$this->load->library('IssuesLib');
+	}
+
+	/**
+	 * Runs issue production job.
+	 * @param studiensemester_kurzbz string job is run for students of a certain semester.
+	 * @param studiengang_kz int job is run for students of certain Studiengang.
+	 */
+	public function run($studiensemester_kurzbz = null, $studiengang_kz = null)
+	{
+		$fehlerKurzbz = $this->plausicheckproducerlib->getFehlerKurzbz();
+
+		$this->logInfo("Plausicheck issue producer job started");
+
+		// get the data returned by Plausicheck
+		foreach ($fehlerKurzbz as $fehler_kurzbz)
+		{
+			// execute the check
+			$this->logInfo("Checking " . $fehler_kurzbz . "...");
+			$plausicheckRes = $this->plausicheckproducerlib->producePlausicheckIssue($fehler_kurzbz, $studiensemester_kurzbz, $studiengang_kz);
+
+			if (isError($plausicheckRes)) $this->logError(getError($plausicheckRes));
+
+			if (hasData($plausicheckRes))
+			{
+				$plausicheckData = getData($plausicheckRes);
+
+				foreach ($plausicheckData as $plausiData)
+				{
+					// get the data needed for issue production
+					$person_id = isset($plausiData['person_id']) ? $plausiData['person_id'] : null;
+					$oe_kurzbz = isset($plausiData['oe_kurzbz']) ? $plausiData['oe_kurzbz'] : null;
+					$fehlertext_params = isset($plausiData['fehlertext_params']) ? $plausiData['fehlertext_params'] : null;
+					$resolution_params = isset($plausiData['resolution_params']) ? $plausiData['resolution_params'] : null;
+
+					// write the issue
+					$addIssueRes = $this->issueslib->addFhcIssue($fehler_kurzbz, $person_id, $oe_kurzbz, $fehlertext_params, $resolution_params);
+
+					// log if error, or log info if inserted new issue
+					if (isError($addIssueRes))
+						$this->logError(getError($addIssueRes));
+					elseif (hasData($addIssueRes) && is_integer(getData($addIssueRes)))
+						$this->logInfo("Plausicheck issue " . $fehler_kurzbz . " successfully produced, person_id: " . $person_id);
+				}
+			}
+		}
+
+		$this->logInfo("Plausicheck issue producer job stopped");
+	}
+}
diff --git a/application/controllers/system/issues/Plausichecks.php b/application/controllers/system/issues/Plausichecks.php
new file mode 100644
index 000000000..748361321
--- /dev/null
+++ b/application/controllers/system/issues/Plausichecks.php
@@ -0,0 +1,133 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+class Plausichecks extends Auth_Controller
+{
+	public function __construct()
+	{
+		parent::__construct(
+			array(
+				'index' => array('system/issues_verwalten:r'),
+				'runChecks' => array('system/issues_verwalten:r')
+			)
+		);
+
+		// Load libraries
+		$this->load->library('issues/PlausicheckProducerLib');
+		$this->load->library('WidgetLib');
+
+		// Load models
+		$this->load->model('system/Fehler_model', 'FehlerModel');
+		$this->load->model('organisation/Studiensemester_model', 'StudiensemesterModel');
+		$this->load->model('organisation/Studiengang_model', 'StudiengangModel');
+	}
+
+	/*
+	 * Get data for filtering the plausichecks and load the view.
+	 */
+	public function index()
+	{
+		$filterData = $this->_getFilterData();
+		$this->load->view('system/issues/plausichecks', $filterData);
+	}
+
+	/**
+	 * Initiate plausichecks run.
+	 */
+	public function runChecks()
+	{
+		$studiensemester_kurzbz = $this->input->get('studiensemester_kurzbz');
+		$studiengang_kz = $this->input->get('studiengang_kz');
+		$fehler_kurzbz = $this->input->get('fehler_kurzbz');
+
+		// issues array for passing issue texts
+		$issueTexts = array();
+		// all fehler kurzbz which are going to be checked
+		$fehlerKurzbz = !isEmptyString($fehler_kurzbz) ? array($fehler_kurzbz) : $this->plausicheckproducerlib->getFehlerKurzbz();
+		// set Studiengang to null if not passed
+		if (isEmptyString($studiengang_kz)) $studiengang_kz = null;
+
+		// get the data returned by Plausicheck
+		foreach ($fehlerKurzbz as $fehler_kurzbz)
+		{
+			// execute the check
+			$issueTexts[$fehler_kurzbz] = array();
+			$plausicheckRes = $this->plausicheckproducerlib->producePlausicheckIssue($fehler_kurzbz, $studiensemester_kurzbz, $studiengang_kz);
+
+			if (isError($plausicheckRes)) $this->terminateWithJsonError(getError($plausicheckRes));
+
+			if (hasData($plausicheckRes))
+			{
+				$plausicheckData = getData($plausicheckRes);
+
+				foreach ($plausicheckData as $plausiData)
+				{
+					// get the data needed for issue production
+					$person_id = isset($plausiData['person_id']) ? $plausiData['person_id'] : null;
+					$oe_kurzbz = isset($plausiData['oe_kurzbz']) ? $plausiData['oe_kurzbz'] : null;
+					$fehlertext_params = isset($plausiData['fehlertext_params']) ? $plausiData['fehlertext_params'] : null;
+					$resolution_params = isset($plausiData['resolution_params']) ? $plausiData['resolution_params'] : null;
+
+					// get Text of the Fehler
+					$this->FehlerModel->addSelect('fehlertext');
+					$fehlerRes = $this->FehlerModel->loadWhere(array('fehler_kurzbz' => $fehler_kurzbz));
+
+					if (isError($fehlerRes)) $this->outputJsonError(getError($fehlerRes));
+
+					// optionally replace fehler parameters in text, output the fehlertext
+					if (hasData($fehlerRes))
+					{
+						$fehlerText = getData($fehlerRes)[0]->fehlertext;
+
+						if (!isEmptyArray($fehlertext_params))
+						{
+							if (count($fehlertext_params) != substr_count($fehlerText, '%s'))
+								$this->terminateWithJsonError('Wrong number of parameters for Fehlertext, fehler_kurzbz ' . $fehler_kurzbz);
+
+							$fehlerText = vsprintf($fehlerText, $fehlertext_params);
+						}
+
+						if (isset($person_id)) $fehlerText .= "; person_id: $person_id";
+						if (isset($oe_kurzbz)) $fehlerText .= "; oe_kurzbz: $oe_kurzbz";
+						$issueTexts[$fehler_kurzbz][] = $fehlerText;
+					}
+				}
+			}
+		}
+
+		$this->outputJsonSuccess($issueTexts);
+	}
+
+	/**
+	 * Get the data needed for filtering for limiting checks.
+	 */
+	private function _getFilterData()
+	{
+		$this->StudiensemesterModel->addOrder('start', 'DESC');
+		$studiensemesterRes = $this->StudiensemesterModel->load();
+
+		if (isError($studiensemesterRes)) show_error(getError($studiensemesterRes));
+
+		$currSemRes = $this->StudiensemesterModel->getAkt();
+
+		if (isError($currSemRes)) show_error(getError($currSemRes));
+
+		$this->StudiengangModel->addSelect('studiengang_kz, tbl_studiengang.bezeichnung, tbl_studiengang.typ,
+			tbl_studiengangstyp.bezeichnung AS typbezeichnung, UPPER(tbl_studiengang.typ::varchar(1) || tbl_studiengang.kurzbz) as kuerzel');
+		$this->StudiengangModel->addJoin('public.tbl_studiengangstyp', 'typ');
+		$this->StudiengangModel->addOrder('kuerzel, tbl_studiengang.bezeichnung, studiengang_kz');
+		$studiengaengeRes = $this->StudiengangModel->loadWhere(array('aktiv' => true));
+
+		if (isError($studiengaengeRes)) show_error(getError($studiengaengeRes));
+
+		$fehlerKurzbz = $this->plausicheckproducerlib->getFehlerKurzbz();
+
+		return array(
+			'semester' => hasData($studiensemesterRes) ? getData($studiensemesterRes) : array(),
+			'currsemester' => hasData($currSemRes) ? getData($currSemRes) : array(),
+			'studiengaenge' => hasData($studiengaengeRes) ? getData($studiengaengeRes) : array(),
+			'fehler' => $fehlerKurzbz
+		);
+	}
+}
diff --git a/application/core/IIssueExistsChecker.php b/application/core/IIssueExistsChecker.php
new file mode 100644
index 000000000..7f5a6b6e5
--- /dev/null
+++ b/application/core/IIssueExistsChecker.php
@@ -0,0 +1,21 @@
+<?php
+
+/**
+ * Interface defining method to implement for issue producer (from core and extensions)
+ */
+interface IIssueExistsChecker
+{
+	/**
+	 * Checks if an issue exists.
+	 * @param array $params parameters needed for issue detection
+	 * @return object with success(true) if issue exists, success(false) otherwise
+	 */
+	public function checkIfIssueExists($paramsForChecking);
+
+	/**
+	 * Produces an issue.
+	 * @param array $params parameters needed for issue detection
+	 * @return object with success(true) if issue exists, success(false) otherwise
+	 */
+	//public function produceIssue($person_id, $oe_kurzbz, $paramsForProducing);
+}
diff --git a/application/core/IssueResolver_Controller.php b/application/core/IssueResolver_Controller.php
index 77d14f408..d325c4e59 100755
--- a/application/core/IssueResolver_Controller.php
+++ b/application/core/IssueResolver_Controller.php
@@ -5,7 +5,8 @@
  */
 abstract class IssueResolver_Controller extends JOB_Controller
 {
-	const ISSUES_FOLDER = 'issues';
+	const CI_PATH = 'application';
+	const ISSUES_FOLDER = 'issues/resolvers';
 	const CHECK_ISSUE_RESOLVED_METHOD_NAME = 'checkIfIssueIsResolved';
 
 	protected $_codeLibMappings;
@@ -43,71 +44,68 @@ abstract class IssueResolver_Controller extends JOB_Controller
 			}
 			else
 			{
-
 				$openIssues = getData($openIssuesRes);
 
 				foreach ($openIssues as $issue)
 				{
-					if (isset($this->_codeLibMappings[$issue->fehlercode]))
+					// ignore if Fehlercode is not in libmappings (shouldn't be checked)
+					if (!isset($this->_codeLibMappings[$issue->fehlercode])) continue;
+
+					$libName = $this->_codeLibMappings[$issue->fehlercode];
+
+					// add person id and oe kurzbz automatically as params, merge it with additional params
+					// decode bewerbung_parameter into assoc array
+					$params = array_merge(
+						array('issue_id' => $issue->issue_id, 'issue_person_id' => $issue->person_id, 'issue_oe_kurzbz' => $issue->oe_kurzbz),
+						isset($issue->behebung_parameter) ? json_decode($issue->behebung_parameter, true) : array()
+					);
+
+					// if called from extension (extension name set), path includes extension names, otherwise it is the core library folder
+					$libRootPath = isset($this->_extensionName) ? 'extensions/' . $this->_extensionName . '/' : '';
+					$issuesLibPath = $libRootPath . self::ISSUES_FOLDER . '/';
+					$issuesLibFilePath = DOC_ROOT . self::CI_PATH . '/' . $libRootPath . 'libraries/' . self::ISSUES_FOLDER . '/' . $libName . '.php';
+
+					// check if library file exists
+					if (!file_exists($issuesLibFilePath))
 					{
-						$libName = $this->_codeLibMappings[$issue->fehlercode];
+						// log error and continue with next issue if not
+						$this->logError("Issue library file " . $issuesLibFilePath . " does not exist");
+						continue;
+					}
 
-						// add person id and oe kurzbz automatically as params, merge it with additional params
-						// decode bewerbung_parameter into assoc array
-						$params = array_merge(
-							array('issue_id' => $issue->issue_id, 'issue_person_id' => $issue->person_id, 'issue_oe_kurzbz' => $issue->oe_kurzbz),
-							isset($issue->behebung_parameter) ? json_decode($issue->behebung_parameter, true) : array()
-						);
+					// load library connected to fehlercode
+					$this->load->library($issuesLibPath . $libName);
 
-						// if called from extension (extension name set), path includes extension names, otherwise it is the core library folder
-						$libRootPath = isset($this->_extensionName) ? 'extensions/' . $this->_extensionName . '/' : '';
-						$issuesLibPath = $libRootPath . self::ISSUES_FOLDER . '/';
-						$issuesLibFilePath = DOC_ROOT . 'application/' . $libRootPath . 'libraries/' . self::ISSUES_FOLDER . '/' . $libName . '.php';
+					$lowercaseLibName = mb_strtolower($libName);
 
-						// check if library file exists
-						if (!file_exists($issuesLibFilePath))
+					// check if method is defined in library class
+					if (!is_callable(array($this->{$lowercaseLibName}, self::CHECK_ISSUE_RESOLVED_METHOD_NAME)))
+					{
+						// log error and continue with next issue if not
+						$this->logError("Method " . self::CHECK_ISSUE_RESOLVED_METHOD_NAME . " is not defined in library $lowercaseLibName");
+						continue;
+					}
+
+					// call the function for checking for issue resolution
+					$issueResolvedRes = $this->{$lowercaseLibName}->{self::CHECK_ISSUE_RESOLVED_METHOD_NAME}($params);
+
+					if (isError($issueResolvedRes))
+					{
+						$this->logError(getError($issueResolvedRes));
+					}
+					else
+					{
+						$issueResolvedData = getData($issueResolvedRes);
+
+						if ($issueResolvedData === true)
 						{
-							// log error and continue with next issue if not
-							$this->logError("Issue library file " . $issuesLibFilePath . " does not exist");
-							continue;
-						}
+							// set issue to resolved if needed
+							$behobenRes = $this->issueslib->setBehoben($issue->issue_id, null);
 
-						// load library connected to fehlercode
-						$this->load->library(
-							$issuesLibPath . $libName
-						);
-
-						$lowercaseLibName = mb_strtolower($libName);
-
-						// check if method is defined in libary class
-						if (!is_callable(array($this->{$lowercaseLibName}, self::CHECK_ISSUE_RESOLVED_METHOD_NAME)))
-						{
-							// log error and continue with next issue if not
-							$this->logError("Method " . self::CHECK_ISSUE_RESOLVED_METHOD_NAME . " is not defined in library $lowercaseLibName");
-							continue;
-						}
-
-						// call the function for checking for issue resolution
-						$issueResolvedRes = $this->{$lowercaseLibName}->{self::CHECK_ISSUE_RESOLVED_METHOD_NAME}($params);
-
-						if (isError($issueResolvedRes))
-						{
-							$this->logError(getError($issueResolvedRes));
-						}
-						else
-						{
-							$issueResolvedData = getData($issueResolvedRes);
-
-							if ($issueResolvedData === true)
-							{
-								// set issue to resolved if needed
-								$behobenRes = $this->issueslib->setBehoben($issue->issue_id, null);
-
-								if (isError($behobenRes))
-									$this->logError(getError($behobenRes));
-								else
-									$this->logInfo("Issue " . $issue->issue_id . " successfully resolved");
-							}
+							if (isError($behobenRes))
+								$this->logError(getError($behobenRes));
+							else
+								$this->logInfo("Issue " . $issue->issue_id . " successfully resolved");
 						}
 					}
 				}
diff --git a/application/libraries/IssuesLib.php b/application/libraries/IssuesLib.php
index d6488bc36..9b3a9de6e 100644
--- a/application/libraries/IssuesLib.php
+++ b/application/libraries/IssuesLib.php
@@ -169,6 +169,9 @@ class IssuesLib
 		return $this->_changeIssueStatus($issue_id, $data, $user);
 	}
 
+	// --------------------------------------------------------------------------------------------------------------
+	// Private methods
+
 	/**
 	 * Changes status of an issue.
 	 * @param int $issue_id
@@ -215,8 +218,15 @@ class IssuesLib
 	 * @param string $inhalt_extern
 	 * @return object success or error
 	 */
-	private function _addIssue($fehlercode, $person_id = null, $oe_kurzbz = null, $fehlertext_params = null, $resolution_params = null, $fehlercode_extern = null, $inhalt_extern = null)
-	{
+	private function _addIssue(
+		$fehlercode,
+		$person_id = null,
+		$oe_kurzbz = null,
+		$fehlertext_params = null,
+		$resolution_params = null,
+		$fehlercode_extern = null,
+		$inhalt_extern = null
+	) {
 		if (isEmptyString($person_id) && isEmptyString($oe_kurzbz))
 			return error("Person_id or oe_kurzbz must be set.");
 
@@ -226,7 +236,15 @@ class IssuesLib
 		if (hasData($fehlerRes))
 		{
 			$fehlertextVorlage = getData($fehlerRes)[0]->fehlertext;
-			$fehlertext = isEmptyArray($fehlertext_params) ? $fehlertextVorlage : vsprintf($fehlertextVorlage, $fehlertext_params);
+
+			$fehlertext = $fehlertextVorlage;
+			if (!isEmptyArray($fehlertext_params))
+			{
+				if (count($fehlertext_params) != substr_count($fehlertextVorlage, '%s'))
+					return error('Wrong number of parameters for Fehlertext, fehler_kurzbz ' . $fehlercode);
+
+				$fehlertext = vsprintf($fehlertextVorlage, $fehlertext_params);
+			}
 
 			$openIssuesCountRes = $this->_ci->IssueModel->getOpenIssueCount($fehlercode, $person_id, $oe_kurzbz, $fehlercode_extern);
 
@@ -252,6 +270,7 @@ class IssuesLib
 							return error("Invalid parameters for resolution");
 					}
 
+					// insert new issue
 					return $this->_ci->IssueModel->insert(
 						array(
 							'fehlercode' => $fehlercode,
@@ -267,8 +286,8 @@ class IssuesLib
 						)
 					);
 				}
-				else
-					return success($openIssueCount);
+				else // return success if issue already exists
+					return success("Issue already exists");
 			}
 			else
 				return error("Number of open issues could not be determined");
diff --git a/application/libraries/issues/PlausicheckLib.php b/application/libraries/issues/PlausicheckLib.php
new file mode 100644
index 000000000..5105169dd
--- /dev/null
+++ b/application/libraries/issues/PlausicheckLib.php
@@ -0,0 +1,1305 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+class PlausicheckLib
+{
+	private $_ci; // Code igniter instance
+	private $_db; // database object
+
+	/**
+	 * Object initialization
+	 */
+	public function __construct()
+	{
+		$this->_ci =& get_instance(); // get ci instance
+
+		// load models
+		$this->_ci->load->model('crm/Prestudent_model', 'PrestudentModel');
+		$this->_ci->load->model('crm/Prestudentstatus_model', 'PrestudentstatusModel');
+		$this->_ci->load->model('organisation/Studiensemester_model', 'StudiensemesterModel');
+
+		// get database for queries
+		$this->_db = new DB_Model();
+	}
+
+	//------------------------------------------------------------------------------------------------------------------
+	// Studiengang checks
+
+	/**
+	 * Studiengang should be the same for prestudent and student.
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param prestudent_id int if check is to be executed only for one prestudent
+	 * @return success with prestudents or error
+	 */
+	public function getStgPrestudentUngleichStgStudent($studiengang_kz = null, $prestudent_id = null)
+	{
+		$params = array();
+
+		$qry = "
+			SELECT
+				pre.person_id, pre.prestudent_id, stg.oe_kurzbz prestudent_stg_oe_kurzbz, student_stg.oe_kurzbz student_stg_oe_kurzbz
+			FROM
+				public.tbl_prestudent pre
+				JOIN public.tbl_student stud USING(prestudent_id)
+				JOIN public.tbl_person pers USING(person_id)
+				JOIN public.tbl_studiengang stg ON pre.studiengang_kz = stg.studiengang_kz
+				JOIN public.tbl_studiengang student_stg ON stud.studiengang_kz = student_stg.studiengang_kz
+			WHERE
+				stud.studiengang_kz != pre.studiengang_kz";
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($prestudent_id))
+		{
+			$qry .= " AND pre.prestudent_id = ?";
+			$params[] = $prestudent_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Orgform of a Studiengang in Studienplan should be the same as orgform of student.
+	 * @param studiensemester_kurzbz string check is to be executed for certain Studiensemester
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param prestudent_id int if check is to be executed only for one prestudent
+	 * @return success with prestudents or error
+	 */
+	public function getOrgformStgUngleichOrgformPrestudent($studiensemester_kurzbz, $studiengang_kz = null, $prestudent_id = null)
+	{
+		$params = array($studiensemester_kurzbz);
+
+		$qry = "
+			SELECT
+				prestudent.person_id, prestudent.prestudent_id, status.studiensemester_kurzbz,
+				studiengang.orgform_kurzbz AS stg_orgform, status.orgform_kurzbz AS student_orgform,
+				prestudent.studiengang_kz AS student_studiengang, stg.oe_kurzbz AS prestudent_stg_oe_kurzbz
+			FROM
+				public.tbl_studiengang studiengang
+				JOIN public.tbl_student student USING(studiengang_kz)
+				JOIN public.tbl_prestudent prestudent USING(prestudent_id)
+				JOIN public.tbl_prestudentstatus status USING(prestudent_id)
+				JOIN public.tbl_benutzer benutzer on(benutzer.uid = student.student_uid)
+				JOIN public.tbl_studiengang stg ON prestudent.studiengang_kz = stg.studiengang_kz
+			WHERE
+				benutzer.aktiv = true
+				AND status.status_kurzbz='Student'
+				AND studiengang.studiengang_kz < 10000
+				AND status.studiensemester_kurzbz = ?
+				AND NOT EXISTS(
+					SELECT 1 FROM lehre.tbl_studienplan
+					JOIN lehre.tbl_studienordnung USING(studienordnung_id)
+					WHERE
+						tbl_studienordnung.studiengang_kz = prestudent.studiengang_kz
+						AND tbl_studienplan.orgform_kurzbz = status.orgform_kurzbz)";
+
+		if (isset($prestudent_id))
+		{
+			$qry .= " AND prestudent.prestudent_id = ?";
+			$params[] = $prestudent_id;
+		}
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		$qry .= "
+			ORDER BY student_uid";
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Students in "mixed" Studiengang should have Orgform.
+	 * @param studiensemester_kurzbz string check is to be executed for certain Studiensemester
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param prestudent_id int if check is to be executed only for one prestudent
+	 * @return success with prestudents or error
+	 */
+	public function getPrestudentMischformOhneOrgform($studiensemester_kurzbz, $studiengang_kz = null, $prestudent_id = null)
+	{
+		$params = array($studiensemester_kurzbz);
+
+		$qry = "
+			SELECT
+				pre.person_id, pre.prestudent_id, stg.oe_kurzbz AS prestudent_stg_oe_kurzbz, status.studiensemester_kurzbz
+			FROM
+				public.tbl_prestudent pre
+				JOIN public.tbl_person USING(person_id)
+				JOIN public.tbl_prestudentstatus status USING(prestudent_id)
+				JOIN public.tbl_studiengang stg USING(studiengang_kz)
+			WHERE
+				status.status_kurzbz IN ('Bewerber', 'Student')
+				AND stg.mischform
+				AND (status.orgform_kurzbz='' OR status.orgform_kurzbz IS NULL)
+				AND status.studiensemester_kurzbz=?";
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($prestudent_id))
+		{
+			$qry .= " AND pre.prestudent_id = ?";
+			$params[] = $prestudent_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Studiengang should be the same for prestudent and studienplan.
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param prestudent_id int if check is to be executed only for one prestudent
+	 * @param studienordnung_id int if check is to be executed only for a certain studienordnung_id
+	 * @return success with prestudents or error
+	 */
+	public function getStgPrestudentUngleichStgStudienplan($studiengang_kz = null, $prestudent_id = null, $studienordnung_id = null)
+	{
+		$params = array();
+
+		$qry = "
+			SELECT
+				DISTINCT ON (ps.prestudent_id) ps.person_id, ps.prestudent_id, stordnung.studienordnung_id,
+				stplan.bezeichnung AS studienplan, stg.oe_kurzbz AS prestudent_stg_oe_kurzbz
+			FROM
+				public.tbl_prestudent ps
+				JOIN public.tbl_prestudentstatus USING(prestudent_id)
+				JOIN lehre.tbl_studienplan stplan USING(studienplan_id)
+				JOIN lehre.tbl_studienordnung stordnung USING(studienordnung_id)
+				JOIN public.tbl_person USING(person_id)
+				JOIN public.tbl_studiengang stg ON ps.studiengang_kz = stg.studiengang_kz
+			WHERE
+				ps.studiengang_kz<>stordnung.studiengang_kz
+				AND stg.melderelevant";
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($prestudent_id))
+		{
+			$qry .= " AND ps.prestudent_id = ?";
+			$params[] = $prestudent_id;
+		}
+
+		if (isset($studienordnung_id))
+		{
+			$qry .= " AND stordnung.studienordnung_id = ?";
+			$params[] = $studienordnung_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	//------------------------------------------------------------------------------------------------------------------
+	// Studentstatus checks
+
+	/**
+	 * Abbrecher cannot be active.
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param prestudent_id int if check is to be executed only for one prestudent
+	 * @return success with prestudents or error
+	 */
+	public function getAbbrecherAktiv($studiengang_kz = null, $prestudent_id = null)
+	{
+		$params = array();
+
+		$qry = "
+			SELECT
+				pre.person_id, pre.prestudent_id, stg.oe_kurzbz AS prestudent_stg_oe_kurzbz
+			FROM
+				public.tbl_prestudentstatus pre_status
+				JOIN public.tbl_prestudent pre USING(prestudent_id)
+				JOIN public.tbl_student student USING(prestudent_id)
+				JOIN public.tbl_benutzer benutzer on(benutzer.uid=student.student_uid)
+				JOIN public.tbl_studiengang stg ON pre.studiengang_kz = stg.studiengang_kz
+			WHERE
+				pre_status.status_kurzbz ='Abbrecher'
+				AND benutzer.aktiv=true";
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($prestudent_id))
+		{
+			$qry .= " AND pre.prestudent_id = ?";
+			$params[] = $prestudent_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * There shouldn't be any status after Abbrecher status.
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param prestudent_id int if check is to be executed only for one prestudent
+	 * @return success with prestudents or error
+	 */
+	public function getStudentstatusNachAbbrecher($studiengang_kz = null, $prestudent_id = null)
+	{
+		$params = array();
+
+		$qry = "
+			SELECT
+				prestudent.person_id, prestudent.prestudent_id, stg.oe_kurzbz AS prestudent_stg_oe_kurzbz
+			FROM
+				public.tbl_student student
+				JOIN public.tbl_prestudent prestudent USING(prestudent_id)
+				JOIN public.tbl_prestudentstatus prestatus USING(prestudent_id)
+				JOIN public.tbl_studiengang stg ON prestudent.studiengang_kz = stg.studiengang_kz
+			WHERE
+				prestatus.status_kurzbz = 'Abbrecher'
+				AND get_rolle_prestudent(prestudent.prestudent_id, prestatus.studiensemester_kurzbz) <> 'Abbrecher'";
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($prestudent_id))
+		{
+			$qry .= " AND prestudent.prestudent_id = ?";
+			$params[] = $prestudent_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Ausbildungssemester of prestudent (lehrverband) must be the same as Ausbildungssemester of prestudentstatus.
+	 * @param studiensemester_kurzbz string check is to be executed for certain Studiensemester
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param prestudent_id int if check is to be executed only for one prestudent
+	 * @return success with prestudents or error
+	 */
+	public function getAusbildungssemPrestudentUngleichAusbildungssemStatus($studiensemester_kurzbz, $studiengang_kz = null, $prestudent_id = null)
+	{
+		$params = array($studiensemester_kurzbz, $studiensemester_kurzbz, $studiensemester_kurzbz);
+
+		$qry = "
+			SELECT
+				DISTINCT(student.student_uid), student.student_uid, prestudent.person_id, prestudent.prestudent_id,
+				status.ausbildungssemester AS status_ausbildungssemester, lv.semester AS student_ausbildungssemester, status.studiensemester_kurzbz,
+				stg.oe_kurzbz AS prestudent_stg_oe_kurzbz
+			FROM
+				public.tbl_student student
+				JOIN public.tbl_studentlehrverband lv USING(student_uid)
+				JOIN public.tbl_prestudent prestudent USING(prestudent_id)
+				JOIN public.tbl_prestudentstatus status USING(prestudent_id)
+				JOIN public.tbl_studiengang stg ON prestudent.studiengang_kz = stg.studiengang_kz
+			WHERE
+				status.studiensemester_kurzbz = ?
+				AND lv.studiensemester_kurzbz = ?
+				AND status.status_kurzbz NOT IN ('Interessent','Bewerber','Aufgenommener','Wartender','Abgewiesener','Unterbrecher')
+				AND get_rolle_prestudent (prestudent_id, ?)='Student'
+				AND status.ausbildungssemester != lv.semester";
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($prestudent_id))
+		{
+			$qry .= " AND prestudent.prestudent_id = ?";
+			$params[] = $prestudent_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Students with active status should have an active Benutzer.
+	 * @param studiensemester_kurzbz string check is to be executed for certain Studiensemester
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param prestudent_id int if check is to be executed only for one prestudent
+	 * @return success with prestudents or error
+	 */
+	public function getInaktiverStudentAktiverStatus($studiensemester_kurzbz, $studiengang_kz = null, $prestudent_id = null)
+	{
+		$aktStudiensemesterRes = $this->_ci->StudiensemesterModel->getAkt();
+
+		if (isError($aktStudiensemesterRes)) return $aktStudiensemesterRes;
+
+		$studiensemester_kurzbz = hasData($aktStudiensemesterRes) ? getData($aktStudiensemesterRes)[0]->studiensemester_kurzbz : '';
+
+		$params = array($studiensemester_kurzbz);
+
+		$qry = "
+			SELECT
+				DISTINCT(student.student_uid), prestudent.person_id, prestudent.prestudent_id, stg.oe_kurzbz AS prestudent_stg_oe_kurzbz
+			FROM
+				public.tbl_benutzer benutzer
+				JOIN public.tbl_student student on(benutzer.uid = student.student_uid)
+				JOIN public.tbl_prestudent prestudent USING(prestudent_id)
+				JOIN public.tbl_studiengang stg ON prestudent.studiengang_kz = stg.studiengang_kz
+			WHERE
+				benutzer.aktiv=false
+				AND EXISTS (SELECT 1 FROM public.tbl_prestudentstatus WHERE prestudent_id = prestudent.prestudent_id AND studiensemester_kurzbz = ?)
+				AND get_rolle_prestudent(prestudent_id, NULL) IN ('Student', 'Diplomand', 'Unterbrecher', 'Praktikant')
+				AND stg.melderelevant
+				AND prestudent.bismelden";
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($prestudent_id))
+		{
+			$qry .= " AND prestudent.prestudent_id = ?";
+			$params[] = $prestudent_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Students of a semester shouldn't start studies before the date of Bismeldung.
+	 * e.g. If student studies in WS2022 datum of status shouldn't be before 15.4.2020
+	 * e.g. If student studies in SS2022 datum of status shouldn't be before 15.11.2022
+	 * @param studiensemester_kurzbz string check is to be executed for certain Studiensemester
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param prestudent_id int if check is to be executed only for one prestudent
+	 * @return success with prestudents or error
+	 */
+	public function getInskriptionVorLetzerBismeldung($studiensemester_kurzbz, $studiengang_kz = null, $prestudent_id = null)
+	{
+		// get Bismeldedatum
+		$datumBis = $this->_getBisdateFromSemester($studiensemester_kurzbz);
+
+		$params = array($datumBis, $studiensemester_kurzbz, $datumBis);
+
+		// get active students
+		$qry = "
+			SELECT
+				DISTINCT ON (student.student_uid) ? AS datum_bismeldung,
+				prestudent.person_id, prestudent.prestudent_id, stg.oe_kurzbz AS prestudent_stg_oe_kurzbz, status.studiensemester_kurzbz
+			FROM
+				public.tbl_benutzer benutzer
+				JOIN public.tbl_student student on(benutzer.uid = student.student_uid)
+				JOIN public.tbl_prestudent prestudent USING(prestudent_id)
+				JOIN public.tbl_prestudentstatus status USING(prestudent_id)
+				JOIN public.tbl_studiengang stg ON prestudent.studiengang_kz = stg.studiengang_kz
+			WHERE
+				benutzer.aktiv=true
+				AND status.studiensemester_kurzbz = ?
+				/* inscription date before date of first student status */
+				AND (
+					SELECT datum
+					FROM public.tbl_prestudentstatus
+					WHERE prestudent_id = prestudent.prestudent_id
+					AND studiensemester_kurzbz = status.studiensemester_kurzbz
+					AND status_kurzbz = 'Student'
+					ORDER BY datum, insertamum, ext_id
+					LIMIT 1
+				) < ?
+				AND stg.melderelevant
+				AND prestudent.bismelden";
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($prestudent_id))
+		{
+			$qry .= " AND prestudent.prestudent_id = ?";
+			$params[] = $prestudent_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Status Dates and status studysemester dates should be in correct order.
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param prestudent_id int if check is to be executed only for one prestudent
+	 * @return success with prestudents or error
+	 */
+	public function getDatumStudiensemesterFalscheReihenfolge($studiengang_kz = null, $prestudent_id = null)
+	{
+		$params = array();
+
+		// all active students with Status student in current semester
+		$qry = "
+			SELECT DISTINCT ON (prestudent_id) *
+			FROM (
+				SELECT
+					prestudent.person_id, prestudent.prestudent_id,
+					stg.studiengang_kz, stg.oe_kurzbz AS prestudent_stg_oe_kurzbz,
+					ROW_NUMBER () OVER (
+						PARTITION BY prestudent.prestudent_id
+						ORDER BY sem.start DESC, status.datum DESC, status.insertamum DESC, status.ext_id DESC
+					) AS reihenfolge_semester,
+					ROW_NUMBER () OVER (
+						PARTITION BY prestudent.prestudent_id
+						ORDER BY status.datum DESC, status.insertamum DESC, status.ext_id DESC
+					) AS reihenfolge_datum
+				FROM
+					public.tbl_student student
+					JOIN public.tbl_benutzer benutzer on(student.student_uid = benutzer.uid)
+					JOIN public.tbl_prestudent prestudent USING(prestudent_id)
+					JOIN public.tbl_prestudentstatus status USING(prestudent_id)
+					JOIN public.tbl_studiensemester sem USING(studiensemester_kurzbz)
+					JOIN public.tbl_studiengang stg ON prestudent.studiengang_kz = stg.studiengang_kz
+				WHERE
+					benutzer.aktiv=true
+					AND status.status_kurzbz='Student'
+			) reihenfolge
+			WHERE reihenfolge_semester <> reihenfolge_datum";
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($prestudent_id))
+		{
+			$qry .= " AND prestudent_id = ?";
+			$params[] = $prestudent_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Students with active Benutzer should have a status in the current semester.
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param prestudent_id int if check is to be executed only for one prestudent
+	 * @return success with prestudents or error
+	 */
+	public function getAktiverStudentOhneStatus($studiengang_kz = null, $prestudent_id = null)
+	{
+		$params = array();
+
+		$qry = "
+			SELECT
+				DISTINCT (student_uid), prestudent.person_id, prestudent.prestudent_id, stg.oe_kurzbz AS prestudent_stg_oe_kurzbz
+			FROM
+				public.tbl_student student
+				JOIN public.tbl_benutzer benutzer on (benutzer.uid = student.student_uid)
+				JOIN public.tbl_prestudent prestudent USING(prestudent_id)
+				JOIN public.tbl_studiengang stg ON prestudent.studiengang_kz = stg.studiengang_kz
+			WHERE
+				benutzer.aktiv=TRUE
+				AND stg.melderelevant
+				AND prestudent.bismelden
+				AND NOT EXISTS (
+					SELECT 1
+					FROM public.tbl_prestudentstatus
+					JOIN public.tbl_studiensemester sem USING (studiensemester_kurzbz)
+					WHERE prestudent_id = prestudent.prestudent_id
+					/* buffer of four months, as status are often entered later */
+					AND sem.ende::date > NOW() - interval '4 months'
+				)";
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($prestudent_id))
+		{
+			$qry .= " AND prestudent.prestudent_id = ?";
+			$params[] = $prestudent_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Studienplan should be valid in current Ausbildungssemester of prestudent.
+	 * @param studiensemester_kurzbz string check is to be executed for certain Studiensemester
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param prestudent_id int if check is to be executed only for one prestudent
+	 * @return success with prestudents or error
+	 */
+	public function getStudienplanUngueltig($studiensemester_kurzbz, $studiengang_kz = null, $prestudent_id = null)
+	{
+		$params = array($studiensemester_kurzbz);
+
+		$qry = "
+			SELECT
+				DISTINCT pre.person_id, pre.prestudent_id,
+				tbl_studienplan.bezeichnung AS studienplan,
+				status.status_kurzbz,
+				status.studiensemester_kurzbz,
+				status.ausbildungssemester,
+				stg.oe_kurzbz AS prestudent_stg_oe_kurzbz
+			FROM
+				public.tbl_prestudent pre
+				JOIN public.tbl_prestudentstatus status USING(prestudent_id)
+				JOIN public.tbl_person USING(person_id)
+				JOIN lehre.tbl_studienplan USING(studienplan_id)
+				JOIN public.tbl_studiengang stg ON pre.studiengang_kz = stg.studiengang_kz
+			WHERE
+				status_kurzbz in('Student', 'Interessent','Bewerber','Aufgenommener')
+				AND NOT EXISTS (
+					SELECT
+						1
+					FROM
+						lehre.tbl_studienplan_semester
+					WHERE
+						studienplan_id=status.studienplan_id
+						AND tbl_studienplan_semester.semester = status.ausbildungssemester
+						AND tbl_studienplan_semester.studiensemester_kurzbz = status.studiensemester_kurzbz
+				)
+				AND status.studiensemester_kurzbz=?
+				AND pre.bismelden
+				AND stg.melderelevant";
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($prestudent_id))
+		{
+			$qry .= " AND tbl_prestudent.prestudent_id = ?";
+			$params[] = $prestudent_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Students with finished studies should have exactly one final exam.
+	 * @param studiensemester_kurzbz string if check is to be executed for certain Studiensemester
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param prestudent_id int if check is to be executed only for one prestudent
+	 * @return success with prestudents or error
+	 */
+	public function getFalscheAnzahlAbschlusspruefungen($studiensemester_kurzbz = null, $studiengang_kz = null, $prestudent_id = null)
+	{
+		$params = array();
+
+		$qry = "
+			SELECT * FROM (
+				SELECT
+					DISTINCT ON(pre.prestudent_id) pre.person_id, pre.prestudent_id, student_uid, stg.oe_kurzbz AS prestudent_stg_oe_kurzbz,
+					(
+						SELECT COUNT(*)
+						FROM lehre.tbl_abschlusspruefung
+						WHERE student_uid = stud.student_uid
+						AND abschlussbeurteilung_kurzbz != 'nicht'
+						AND abschlussbeurteilung_kurzbz IS NOT NULL
+					) AS anzahl_abschlusspruefungen
+				FROM
+					public.tbl_prestudent pre
+					JOIN public.tbl_student stud USING(prestudent_id)
+					JOIN public.tbl_prestudentstatus status USING(prestudent_id)
+					JOIN public.tbl_studiengang stg ON pre.studiengang_kz = stg.studiengang_kz
+				WHERE
+					status_kurzbz = 'Absolvent'
+					AND pre.bismelden
+					AND stg.melderelevant
+					AND NOT EXISTS ( /* exclude gs */
+						SELECT 1
+						FROM bis.tbl_mobilitaet
+						WHERE prestudent_id = pre.prestudent_id
+						AND studiensemester_kurzbz = status.studiensemester_kurzbz
+					)";
+
+		if (isset($studiensemester_kurzbz))
+		{
+			$qry .= " AND status.studiensemester_kurzbz = ?";
+			$params[] = $studiensemester_kurzbz;
+		}
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($prestudent_id))
+		{
+			$qry .= " AND pre.prestudent_id = ?";
+			$params[] = $prestudent_id;
+		}
+
+		$qry .= ") studenten
+			WHERE anzahl_abschlusspruefungen != 1";
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Date of final exam shouldn't be missing for Absolvent.
+	 * @param studiensemester_kurzbz string if check is to be executed for certain Studiensemester
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param abschlusspruefung_id int if check is to be executed for a certain Abschlussprüfung
+	 * @return success with prestudents or error
+	 */
+	public function getDatumAbschlusspruefungFehlt($studiensemester_kurzbz = null, $studiengang_kz = null, $abschlusspruefung_id = null)
+	{
+		$results = array();
+
+		$pruefungenRes = $this->_getInvalidAbschlusspruefungen($studiensemester_kurzbz, $studiengang_kz, $abschlusspruefung_id);
+
+		if (isError($pruefungenRes)) return $pruefungenRes;
+
+		if (hasData($pruefungenRes))
+		{
+			$pruefungen = getData($pruefungenRes);
+
+			foreach ($pruefungen as $pruefung)
+			{
+				if (isEmptyString($pruefung->datum)) $results[] = $pruefung;
+			}
+		}
+
+		return success($results);
+	}
+
+	/**
+	 * Date of sponsion shouldn't be missing for Absolvent.
+	 * @param studiensemester_kurzbz string check is to be executed for certain Studiensemester
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param abschlusspruefung_id int if check is to be executed only for a certain Abschlussprüfung
+	 * @return success with prestudents or error
+	 */
+	public function getDatumSponsionFehlt($studiensemester_kurzbz = null, $studiengang_kz = null, $abschlusspruefung_id = null)
+	{
+		$results = array();
+
+		$pruefungenRes = $this->_getInvalidAbschlusspruefungen($studiensemester_kurzbz, $studiengang_kz, $abschlusspruefung_id);
+
+		if (isError($pruefungenRes)) return $pruefungenRes;
+
+		if (hasData($pruefungenRes))
+		{
+			$pruefungen = getData($pruefungenRes);
+
+			foreach ($pruefungen as $pruefung)
+			{
+				if (isEmptyString($pruefung->sponsion)) $results[] = $pruefung;
+			}
+		}
+
+		return success($results);
+	}
+
+	/**
+	 * Bewerber should have participated in Reihungstest.
+	 * @param studiensemester_kurzbz string check is to be executed for certain Studiensemester
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param prestudent_id int if check is to be executed only for one prestudent
+	 * @return success with prestudents or error
+	 */
+	public function getBewerberNichtZumRtAngetreten($studiensemester_kurzbz, $studiengang_kz = null, $prestudent_id = null)
+	{
+		$previousStudiensemesterRes = $this->_ci->StudiensemesterModel->getPreviousFrom($studiensemester_kurzbz);
+
+		if (isError($previousStudiensemesterRes)) return $previousStudiensemesterRes;
+
+		$params = array($studiensemester_kurzbz);
+
+		$qry = "
+			SELECT
+				prestudent.person_id, prestudent.prestudent_id, stg.oe_kurzbz AS prestudent_stg_oe_kurzbz, status.studiensemester_kurzbz
+			FROM
+				public.tbl_prestudent prestudent
+				JOIN public.tbl_prestudentstatus status ON(prestudent.prestudent_id=status.prestudent_id)
+				JOIN public.tbl_person USING(person_id)
+				LEFT JOIN bis.tbl_orgform USING(orgform_kurzbz)
+				JOIN public.tbl_studiengang stg USING(studiengang_kz)
+			WHERE
+				status_kurzbz='Bewerber'
+				AND reihungstestangetreten=false
+				AND stg.melderelevant
+				AND prestudent.bismelden";
+
+		if (hasData($previousStudiensemesterRes))
+		{
+			$previousStudiensemester = getData($previousStudiensemesterRes)[0]->studiensemester_kurzbz;
+			$qry .= " AND (studiensemester_kurzbz=? OR studiensemester_kurzbz=?)";
+			$params[] = $previousStudiensemester;
+		}
+		else
+		{
+			$qry .= " AND studiensemester_kurzbz=?";
+		}
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($prestudent_id))
+		{
+			$qry .= " AND prestudent.prestudent_id = ?";
+			$params[] = $prestudent_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Current Ausbildungssemester shouldn't be 0.
+	 * @param studiensemester_kurzbz string check is to be executed for certain Studiensemester
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param prestudent_id int if check is to be executed only for one prestudent
+	 * @return success with prestudents or error
+	 */
+	public function getAktSemesterNull($studiensemester_kurzbz, $studiengang_kz = null, $prestudent_id = null)
+	{
+		$params = array($studiensemester_kurzbz);
+
+		$qry = "
+			SELECT
+				DISTINCT pre.person_id, pre.prestudent_id, stg.oe_kurzbz AS prestudent_stg_oe_kurzbz, prestat.studiensemester_kurzbz
+			FROM
+				public.tbl_prestudent pre
+				JOIN public.tbl_prestudentstatus prestat USING(prestudent_id)
+				JOIN public.tbl_studiengang stg USING(studiengang_kz)
+			WHERE
+				prestat.status_kurzbz != 'Incoming'
+				AND prestat.studiensemester_kurzbz = ?
+				AND ausbildungssemester = 0
+				AND stg.melderelevant
+				AND pre.bismelden";
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($prestudent_id))
+		{
+			$qry .= " AND pre.prestudent_id = ?";
+			$params[] = $prestudent_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Prestudent should have a final status.
+	 * @param studiensemester_kurzbz string if check is to be executed for certain Studiensemester
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param prestudent_id int if check is to be executed only for one prestudent
+	 * @return success with prestudents or error
+	 */
+	public function getAbschlussstatusFehlt($studiensemester_kurzbz = null, $studiengang_kz = null, $prestudent_id = null)
+	{
+		$params = array();
+
+		$qry = "
+			SELECT
+				DISTINCT ON (pre.prestudent_id)
+				pre.person_id, pre.prestudent_id, stg.oe_kurzbz AS prestudent_stg_oe_kurzbz, status.studiensemester_kurzbz
+			FROM
+				public.tbl_prestudent pre
+				JOIN public.tbl_person USING(person_id)
+				JOIN public.tbl_prestudentstatus status USING(prestudent_id)
+				JOIN public.tbl_studiengang stg USING(studiengang_kz)
+			WHERE
+				NOT EXISTS( /*student does not study anymore*/
+					SELECT
+						1
+					FROM
+						public.tbl_prestudentstatus ps
+						JOIN public.tbl_studiensemester USING(studiensemester_kurzbz)
+					WHERE
+						prestudent_id=pre.prestudent_id
+						/* 4 months: There might be Diplomanden, in summer months end status is often not entered yet */
+						AND tbl_studiensemester.ende>now() - interval '4 months'
+				)
+				/* check only valid begininng with 2018 */
+				AND '2018-01-01'<(SELECT max(datum) FROM public.tbl_prestudentstatus WHERE prestudent_id=pre.prestudent_id)
+				AND NOT EXISTS( /* no end status */
+					SELECT 1
+					FROM public.tbl_prestudentstatus ps
+					WHERE
+						prestudent_id=pre.prestudent_id
+						AND status_kurzbz IN('Abbrecher','Abgewiesener','Absolvent','Incoming')
+				)
+				AND stg.melderelevant
+				AND pre.bismelden";
+
+		if (isset($studiensemester_kurzbz))
+		{
+			$prevStudiensemesterRes = $this->_ci->StudiensemesterModel->getPreviousFrom($studiensemester_kurzbz);
+
+			if (isError($prevStudiensemesterRes)) return $prevStudiensemesterRes;
+
+			if (hasData($prevStudiensemesterRes))
+			{
+				// if Studiensemester given, check only if has status in current or previous semester
+				$prevStudiensemester = getData($prevStudiensemesterRes)[0]->studiensemester_kurzbz;
+				$qry .= " AND EXISTS (
+							SELECT 1
+							FROM public.tbl_prestudentstatus ps
+							WHERE studiensemester_kurzbz IN (?, ?)
+							AND ps.prestudent_id = pre.prestudent_id
+						)";
+				$params[] = $prevStudiensemester;
+				$params[] = $studiensemester_kurzbz;
+			}
+		}
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($prestudent_id))
+		{
+			$qry .= " AND pre.prestudent_id = ?";
+			$params[] = $prestudent_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	//------------------------------------------------------------------------------------------------------------------
+	// Person checks
+
+	/**
+	 * Birthdate is too long ago.
+	 * @param studiensemester_kurzbz string if check is to be executed for certain Studiensemester
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param person_id int if check is to be executed only for one person
+	 * @return success with prestudents or error
+	 */
+	public function getGbDatumWeitZurueck($studiensemester_kurzbz = null, $studiengang_kz = null, $person_id = null)
+	{
+		$params = array();
+
+		$qry = "
+			SELECT
+				pers.person_id
+			FROM
+				public.tbl_person pers
+			WHERE
+				pers.gebdatum < '1920-01-01'
+				AND EXISTS (
+					SELECT 1
+					FROM public.tbl_prestudent
+					JOIN public.tbl_prestudentstatus status USING(prestudent_id)
+					JOIN public.tbl_studiengang stg USING(studiengang_kz)
+					WHERE person_id = pers.person_id";
+
+		if (isset($studiensemester_kurzbz))
+		{
+			$qry .= " AND status.studiensemester_kurzbz = ?";
+			$params[] = $studiensemester_kurzbz;
+		}
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		$qry .= ")";
+
+		if (isset($person_id))
+		{
+			$qry .= " AND pers.person_id = ?";
+			$params[] = $person_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Nation is not Austria, but address has austrian Gemeinde.
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param person_id int if check is to be executed only for one person
+	 * @return success with prestudents or error
+	 */
+	public function getNationNichtOesterreichAberGemeinde($studiengang_kz = null, $person_id = null)
+	{
+		$params = array();
+
+		$qry = "SELECT DISTINCT tbl_person.person_id, adr.gemeinde, adr.adresse_id
+				FROM
+					public.tbl_adresse adr
+					JOIN public.tbl_prestudent USING(person_id)
+					JOIN public.tbl_person USING(person_id)
+					JOIN public.tbl_student USING(prestudent_id)
+					JOIN public.tbl_benutzer ON(uid=student_uid)
+					JOIN public.tbl_studiengang stg ON tbl_prestudent.studiengang_kz = stg.studiengang_kz
+				WHERE
+					adr.nation!='A'
+					AND tbl_benutzer.aktiv
+					AND gemeinde NOT IN ('Münster')
+					AND EXISTS(SELECT 1 FROM bis.tbl_gemeinde WHERE name = adr.gemeinde)";
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($person_id))
+		{
+			$qry .= " AND tbl_person.person_id = ?";
+			$params[] = $person_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Students should have exactly one home address.
+	 * @param studiensemester_kurzbz string check is to be executed for certain Studiensemester
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param person_id int if check is to be executed only for one person
+	 * @return success with prestudents or error
+	 */
+	public function getFalscheAnzahlHeimatadressen($studiensemester_kurzbz = null, $studiengang_kz = null, $person_id = null)
+	{
+		$params = array();
+
+		$qry = "
+			SELECT
+				DISTINCT person_id
+			FROM
+				(
+					SELECT person_id, COUNT(adresse_id) AS anzahl_adressen
+					FROM public.tbl_adresse addr
+					WHERE heimatadresse IS TRUE
+					GROUP BY person_id
+				) adressen
+				JOIN public.tbl_person USING(person_id)
+				JOIN public.tbl_prestudent pre USING(person_id)
+				JOIN public.tbl_prestudentstatus status USING(prestudent_id)
+				JOIN public.tbl_student USING(prestudent_id)
+				JOIN public.tbl_studiengang stg ON pre.studiengang_kz = stg.studiengang_kz
+			WHERE
+				anzahl_adressen != 1
+				AND stg.melderelevant
+				AND pre.bismelden";
+
+		if (isset($studiensemester_kurzbz))
+		{
+			$qry .= " AND status.studiensemester_kurzbz = ?";
+			$params[] = $studiensemester_kurzbz;
+		}
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($person_id))
+		{
+			$qry .= " AND person_id = ?";
+			$params[] = $person_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Students should have exactly one delivery address.
+	 * @param studiensemester_kurzbz string if check is to be executed for certain Studiensemester
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param person_id int if check is to be executed only for one person
+	 * @return success with prestudents or error
+	 */
+	public function getFalscheAnzahlZustelladressen($studiensemester_kurzbz = null, $studiengang_kz = null, $person_id = null)
+	{
+		$params = array();
+
+		$qry = "
+			SELECT
+				DISTINCT person_id
+			FROM
+				(
+					SELECT person_id, COUNT(adresse_id) AS anzahl_adressen
+					FROM public.tbl_adresse addr
+					WHERE zustelladresse IS TRUE
+					GROUP BY person_id
+				) adressen
+				JOIN public.tbl_person USING(person_id)
+				JOIN public.tbl_prestudent pre USING(person_id)
+				JOIN public.tbl_prestudentstatus status USING(prestudent_id)
+				JOIN public.tbl_student USING(prestudent_id)
+				JOIN public.tbl_studiengang stg ON pre.studiengang_kz = stg.studiengang_kz
+			WHERE
+				anzahl_adressen != 1
+				AND stg.melderelevant
+				AND pre.bismelden";
+
+		if (isset($studiensemester_kurzbz))
+		{
+			$qry .= " AND status.studiensemester_kurzbz = ?";
+			$params[] = $studiensemester_kurzbz;
+		}
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($person_id))
+		{
+			$qry .= " AND person_id = ?";
+			$params[] = $person_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	//------------------------------------------------------------------------------------------------------------------
+	// I/O checks
+
+	/**
+	 * Incoming shouldn't have austrian home address.
+	 * @param studiensemester_kurzbz string check is to be executed for certain Studiensemester
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param person_id int if check is to be executed only for one person
+	 * @return success with prestudents or error
+	 */
+	public function getIncomingHeimatNationOesterreich($studiensemester_kurzbz, $studiengang_kz = null, $person_id = null)
+	{
+		$params = array($studiensemester_kurzbz);
+
+		$qry = "
+			SELECT
+				DISTINCT pers.person_id, status.studiensemester_kurzbz
+			FROM
+				public.tbl_prestudent pre
+				JOIN public.tbl_prestudentstatus status USING(prestudent_id)
+				JOIN public.tbl_person pers USING(person_id)
+				JOIN public.tbl_adresse addr USING(person_id)
+				JOIN public.tbl_studiengang stg USING(studiengang_kz)
+			WHERE
+				status.status_kurzbz = 'Incoming'
+				AND addr.nation = 'A'
+				AND addr.heimatadresse
+				AND status.studiensemester_kurzbz = ?
+				AND stg.melderelevant
+				AND pre.bismelden";
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($person_id))
+		{
+			$qry .= " AND pers.person_id = ?";
+			$params[] = $person_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Incoming should have IN/OUT data.
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param prestudent_id int if check is to be executed only for one prestudent
+	 * @return success with prestudents or error
+	 */
+	public function getIncomingOhneIoDatensatz($studiengang_kz = null, $prestudent_id = null)
+	{
+		$params = array();
+
+		$qry = "
+			SELECT
+				DISTINCT ON(student_uid, nachname, vorname)
+				tbl_person.person_id,
+				tbl_prestudent.prestudent_id,
+				stg.oe_kurzbz AS prestudent_stg_oe_kurzbz
+			FROM
+				public.tbl_student
+				JOIN public.tbl_benutzer ON(student_uid=uid)
+				JOIN public.tbl_person USING(person_id)
+				JOIN public.tbl_prestudent USING(prestudent_id)
+				JOIN public.tbl_prestudentstatus ON(tbl_prestudent.prestudent_id=tbl_prestudentstatus.prestudent_id)
+				JOIN public.tbl_studiengang stg ON(stg.studiengang_kz=tbl_student.studiengang_kz)
+			WHERE
+				bismelden=TRUE
+				AND status_kurzbz='Incoming' AND NOT EXISTS (SELECT 1 FROM bis.tbl_bisio WHERE student_uid=tbl_student.student_uid)
+				AND stg.melderelevant";
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($prestudent_id))
+		{
+			$qry .= " AND tbl_prestudent.prestudent_id = ?";
+			$params[] = $prestudent_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Incoming or gemeinsame Studien students should not receive funding (not be förderrelevant).
+	 * @param studiensemester_kurzbz string check is to be executed for certain Studiensemester
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param prestudent_id int if check is to be executed only for one prestudent
+	 * @return object success or error
+	 */
+	public function getIncomingOrGsFoerderrelevant($studiensemester_kurzbz = null, $studiengang_kz = null, $prestudent_id = null)
+	{
+		$params = array();
+
+		$qry = "
+			SELECT
+				DISTINCT ON(prestudent_id)
+				pers.person_id,
+				ps.prestudent_id,
+				stg.oe_kurzbz AS prestudent_stg_oe_kurzbz
+			FROM
+				public.tbl_student stud
+				JOIN public.tbl_benutzer ON(student_uid=uid)
+				JOIN public.tbl_person pers USING(person_id)
+				JOIN public.tbl_prestudent ps USING(prestudent_id)
+				JOIN public.tbl_prestudentstatus status USING(prestudent_id)
+				JOIN public.tbl_studiengang stg ON(stg.studiengang_kz=stud.studiengang_kz)
+			WHERE
+				(
+					status.status_kurzbz = 'Incoming'
+					OR EXISTS (
+						SELECT 1
+						FROM
+							bis.tbl_mobilitaet
+							JOIN public.tbl_prestudent USING(prestudent_id)
+						WHERE
+							prestudent_id = ps.prestudent_id
+							AND gsstudientyp_kurzbz = 'Extern'
+					)
+				)
+				AND (ps.foerderrelevant <> FALSE OR ps.foerderrelevant IS NULL)
+				AND bismelden=TRUE
+				AND stg.melderelevant";
+
+		if (isset($studiensemester_kurzbz))
+		{
+			$qry .= " AND status.studiensemester_kurzbz = ?";
+			$params[] = $studiensemester_kurzbz;
+		}
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($prestudent_id))
+		{
+			$qry .= " AND ps.prestudent_id = ?";
+			$params[] = $prestudent_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	//------------------------------------------------------------------------------------------------------------------
+	// Private methods
+
+	/**
+	 * Get final exams in a semester which are invalid (e.g. missing data)
+	 * @param studiensemester_kurzbz string if check is to be executed for certain Studiengang
+	 * @param studiengang_kz int if check is to be executed for certain Studiengang
+	 * @param abschlusspruefung_id int if check is to be executed for certain Abschlussprüfung
+	 */
+	private function _getInvalidAbschlusspruefungen($studiensemester_kurzbz = null, $studiengang_kz = null, $abschlusspruefung_id = null)
+	{
+		$params = array();
+
+		$qry = "
+			SELECT
+				pre.person_id, pre.prestudent_id,
+				pruefung.sponsion, pruefung.datum, pruefung.abschlusspruefung_id,
+				stg.oe_kurzbz AS prestudent_stg_oe_kurzbz
+			FROM
+				public.tbl_prestudent pre
+				JOIN public.tbl_student stud USING(prestudent_id)
+				JOIN public.tbl_prestudentstatus prestatus USING(prestudent_id)
+				JOIN public.tbl_studiengang stg ON pre.studiengang_kz = stg.studiengang_kz
+				JOIN lehre.tbl_abschlusspruefung pruefung ON stud.student_uid = pruefung.student_uid
+			WHERE
+				status_kurzbz = 'Absolvent'
+				AND NOT EXISTS ( /* exclude gs */
+					SELECT 1
+					FROM bis.tbl_mobilitaet
+					WHERE prestudent_id = pre.prestudent_id
+					AND studiensemester_kurzbz = prestatus.studiensemester_kurzbz
+				)
+				AND abschlussbeurteilung_kurzbz!='nicht'
+				AND abschlussbeurteilung_kurzbz IS NOT NULL
+				AND (pruefung.datum IS NULL OR pruefung.sponsion IS NULL)
+				AND pre.bismelden
+				AND stg.melderelevant";
+
+		if (isset($studiensemester_kurzbz))
+		{
+			$qry .= " AND prestatus.studiensemester_kurzbz = ?";
+			$params[] = $studiensemester_kurzbz;
+		}
+
+		if (isset($studiengang_kz))
+		{
+			$qry .= " AND stg.studiengang_kz = ?";
+			$params[] = $studiengang_kz;
+		}
+
+		if (isset($abschlusspruefung_id))
+		{
+			$qry .= " AND pruefung.abschlusspruefung_id = ?";
+			$params[] = $abschlusspruefung_id;
+		}
+
+		return $this->_db->execReadOnlyQuery($qry, $params);
+	}
+
+	/**
+	 * Gets Bismeldedate from Studiensemester.
+	 * @param studiensemester_kurzbz string
+	 */
+	private function _getBisdateFromSemester($studiensemester_kurzbz)
+	{
+		$semesterYear = substr($studiensemester_kurzbz, 2, 6);
+		$semesterType = substr($studiensemester_kurzbz, 0, 2);
+
+		if ($semesterType == 'SS')
+		{
+			return date_format(date_create(($semesterYear - 1)."-11-15"), 'Y-m-d');
+		}
+
+		if ($semesterType == 'WS')
+		{
+			return date_format(date_create($semesterYear."-04-15"), 'Y-m-d');
+		}
+	}
+}
diff --git a/application/libraries/issues/PlausicheckProducerLib.php b/application/libraries/issues/PlausicheckProducerLib.php
new file mode 100644
index 000000000..c1e15151f
--- /dev/null
+++ b/application/libraries/issues/PlausicheckProducerLib.php
@@ -0,0 +1,102 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+class PlausicheckProducerLib
+{
+	const CI_LIBRARY_PATH = 'application/libraries';
+	const PLAUSI_ISSUES_FOLDER = 'issues/plausichecks';
+	const EXECUTE_PLAUSI_CHECK_METHOD_NAME = 'executePlausiCheck';
+
+	private $_ci; // ci instance
+	private $_currentStudiensemester; // current Studiensemester
+
+	// set fehler which can be produced by the job
+	// structure: fehler_kurzbz => class (library) name for resolving
+	private $_fehlerLibMappings = array(
+		'AbbrecherAktiv' => 'AbbrecherAktiv',
+		'AbschlussstatusFehlt' => 'AbschlussstatusFehlt',
+		'AktSemesterNull' => 'AktSemesterNull',
+		'AktiverStudentOhneStatus' => 'AktiverStudentOhneStatus',
+		'AusbildungssemPrestudentUngleichAusbildungssemStatus' => 'AusbildungssemPrestudentUngleichAusbildungssemStatus',
+		'BewerberNichtZumRtAngetreten' => 'BewerberNichtZumRtAngetreten',
+		'DatumAbschlusspruefungFehlt' => 'DatumAbschlusspruefungFehlt',
+		'DatumSponsionFehlt' => 'DatumSponsionFehlt',
+		'DatumStudiensemesterFalscheReihenfolge' => 'DatumStudiensemesterFalscheReihenfolge',
+		'FalscheAnzahlAbschlusspruefungen' => 'FalscheAnzahlAbschlusspruefungen',
+		'FalscheAnzahlHeimatadressen' => 'FalscheAnzahlHeimatadressen',
+		'FalscheAnzahlZustelladressen' => 'FalscheAnzahlZustelladressen',
+		'GbDatumWeitZurueck' => 'GbDatumWeitZurueck',
+		'InaktiverStudentAktiverStatus' => 'InaktiverStudentAktiverStatus',
+		'IncomingHeimatNationOesterreich' => 'IncomingHeimatNationOesterreich',
+		'IncomingOhneIoDatensatz' => 'IncomingOhneIoDatensatz',
+		'IncomingOrGsFoerderrelevant' => 'IncomingOrGsFoerderrelevant',
+		'InskriptionVorLetzerBismeldung' => 'InskriptionVorLetzerBismeldung',
+		'NationNichtOesterreichAberGemeinde' => 'NationNichtOesterreichAberGemeinde',
+		'OrgformStgUngleichOrgformPrestudent' => 'OrgformStgUngleichOrgformPrestudent',
+		'PrestudentMischformOhneOrgform' => 'PrestudentMischformOhneOrgform',
+		'StgPrestudentUngleichStgStudienplan' => 'StgPrestudentUngleichStgStudienplan',
+		'StgPrestudentUngleichStgStudent' => 'StgPrestudentUngleichStgStudent',
+		'StudentstatusNachAbbrecher' => 'StudentstatusNachAbbrecher'
+		//'StudienplanUngueltig' => 'StudienplanUngueltig'
+	);
+
+	public function __construct()
+	{
+		$this->_ci =& get_instance(); // get ci instance
+
+		// load models
+		$this->_ci->load->model('organisation/studiensemester_model', 'StudiensemesterModel');
+
+		// get current Studiensemester
+		$studiensemesterRes = $this->_ci->StudiensemesterModel->getAkt();
+		if (hasData($studiensemesterRes)) $this->_currentStudiensemester = getData($studiensemesterRes)[0]->studiensemester_kurzbz;
+	}
+
+	/**
+	 * Executes check for a fehler_kurzbz, returns the result.
+	 * @param $fehler_kurzbz string
+	 * @param $studiensemester_kurzbz string optionally needed for issue production
+	 * @param $studiengang_kz int optionally needed for issue production
+	 */
+	public function producePlausicheckIssue($fehler_kurzbz, $studiensemester_kurzbz = null, $studiengang_kz = null)
+	{
+		$libName = $this->_fehlerLibMappings[$fehler_kurzbz];
+
+		// get Studiensemester
+		if (isEmptyString($studiensemester_kurzbz)) $studiensemester_kurzbz = $this->_currentStudiensemester;
+
+		// get path of library for issue to be produced
+		$issuesLibPath = DOC_ROOT . self::CI_LIBRARY_PATH . '/' . self::PLAUSI_ISSUES_FOLDER . '/';
+		$issuesLibFilePath = $issuesLibPath . $libName . '.php';
+
+		// check if library file exists
+		if (!file_exists($issuesLibFilePath)) return error("Issue library file " . $issuesLibFilePath . " does not exist");
+
+		// load library connected to fehlercode
+		$this->_ci->load->library(self::PLAUSI_ISSUES_FOLDER . '/'.$libName);
+
+		$lowercaseLibName = mb_strtolower($libName);
+
+		// check if method is defined in library class
+		if (!is_callable(array($this->_ci->{$lowercaseLibName}, self::EXECUTE_PLAUSI_CHECK_METHOD_NAME)))
+			return error("Method " . self::EXECUTE_PLAUSI_CHECK_METHOD_NAME . " is not defined in library $lowercaseLibName");
+
+		// pass the data needed for issue check
+		$paramsForCheck = array(
+			'studiensemester_kurzbz' => $studiensemester_kurzbz,
+			'studiengang_kz' => $studiengang_kz
+		);
+
+		// call the function for checking for issue production
+		return $this->_ci->{$lowercaseLibName}->{self::EXECUTE_PLAUSI_CHECK_METHOD_NAME}($paramsForCheck);
+	}
+
+	/**
+	 * Gets all fehler_kurzbz for fehler which need to be checked.
+	 */
+	public function getFehlerKurzbz()
+	{
+		return array_keys($this->_fehlerLibMappings);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/AbbrecherAktiv.php b/application/libraries/issues/plausichecks/AbbrecherAktiv.php
new file mode 100644
index 000000000..cc6e2996a
--- /dev/null
+++ b/application/libraries/issues/plausichecks/AbbrecherAktiv.php
@@ -0,0 +1,43 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class AbbrecherAktiv extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getAbbrecherAktiv($studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array('prestudent_id' => $prestudent->prestudent_id),
+					'resolution_params' => array('prestudent_id' => $prestudent->prestudent_id)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/AbschlussstatusFehlt.php b/application/libraries/issues/plausichecks/AbschlussstatusFehlt.php
new file mode 100644
index 000000000..66615220a
--- /dev/null
+++ b/application/libraries/issues/plausichecks/AbschlussstatusFehlt.php
@@ -0,0 +1,44 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class AbschlussstatusFehlt extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiensemester_kurzbz = isset($params['studiensemester_kurzbz']) ? $params['studiensemester_kurzbz'] : null;
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getAbschlussstatusFehlt($studiensemester_kurzbz, $studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array('prestudent_id' => $prestudent->prestudent_id),
+					'resolution_params' => array('prestudent_id' => $prestudent->prestudent_id)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/AktSemesterNull.php b/application/libraries/issues/plausichecks/AktSemesterNull.php
new file mode 100644
index 000000000..d55506d68
--- /dev/null
+++ b/application/libraries/issues/plausichecks/AktSemesterNull.php
@@ -0,0 +1,50 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class AktSemesterNull extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiensemester_kurzbz = isset($params['studiensemester_kurzbz']) ? $params['studiensemester_kurzbz'] : null;
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getAktSemesterNull($studiensemester_kurzbz, $studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array(
+						'prestudent_id' => $prestudent->prestudent_id,
+						'studiensemester_kurzbz' => $prestudent->studiensemester_kurzbz
+					),
+					'resolution_params' => array(
+						'prestudent_id' => $prestudent->prestudent_id,
+						'studiensemester_kurzbz' => $prestudent->studiensemester_kurzbz
+					)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/AktiverStudentOhneStatus.php b/application/libraries/issues/plausichecks/AktiverStudentOhneStatus.php
new file mode 100644
index 000000000..2dfd9f866
--- /dev/null
+++ b/application/libraries/issues/plausichecks/AktiverStudentOhneStatus.php
@@ -0,0 +1,43 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class AktiverStudentOhneStatus extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getAktiverStudentOhneStatus($studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array('prestudent_id' => $prestudent->prestudent_id),
+					'resolution_params' => array('prestudent_id' => $prestudent->prestudent_id)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/AusbildungssemPrestudentUngleichAusbildungssemStatus.php b/application/libraries/issues/plausichecks/AusbildungssemPrestudentUngleichAusbildungssemStatus.php
new file mode 100644
index 000000000..ca967a97f
--- /dev/null
+++ b/application/libraries/issues/plausichecks/AusbildungssemPrestudentUngleichAusbildungssemStatus.php
@@ -0,0 +1,56 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class AusbildungssemPrestudentUngleichAusbildungssemStatus extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiensemester_kurzbz = isset($params['studiensemester_kurzbz']) ? $params['studiensemester_kurzbz'] : null;
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getAusbildungssemPrestudentUngleichAusbildungssemStatus(
+			$studiensemester_kurzbz,
+			$studiengang_kz
+		);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array(
+						'status_ausbildungssemester' => $prestudent->status_ausbildungssemester,
+						'student_ausbildungssemester' => $prestudent->student_ausbildungssemester,
+						'student_uid' => $prestudent->student_uid,
+						'prestudent_id' => $prestudent->prestudent_id,
+						'studiensemester_kurzbz' => $prestudent->studiensemester_kurzbz
+					),
+					'resolution_params' => array(
+						'prestudent_id' => $prestudent->prestudent_id,
+						'studiensemester_kurzbz' => $prestudent->studiensemester_kurzbz
+					)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/BewerberNichtZumRtAngetreten.php b/application/libraries/issues/plausichecks/BewerberNichtZumRtAngetreten.php
new file mode 100644
index 000000000..35d954236
--- /dev/null
+++ b/application/libraries/issues/plausichecks/BewerberNichtZumRtAngetreten.php
@@ -0,0 +1,47 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class BewerberNichtZumRtAngetreten extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiensemester_kurzbz = isset($params['studiensemester_kurzbz']) ? $params['studiensemester_kurzbz'] : null;
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getBewerberNichtZumRtAngetreten($studiensemester_kurzbz, $studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array('prestudent_id' => $prestudent->prestudent_id),
+					'resolution_params' => array(
+						'studiensemester_kurzbz' => $prestudent->studiensemester_kurzbz,
+						'prestudent_id' => $prestudent->prestudent_id
+					)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/DatumAbschlusspruefungFehlt.php b/application/libraries/issues/plausichecks/DatumAbschlusspruefungFehlt.php
new file mode 100644
index 000000000..7a2555b69
--- /dev/null
+++ b/application/libraries/issues/plausichecks/DatumAbschlusspruefungFehlt.php
@@ -0,0 +1,47 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class DatumAbschlusspruefungFehlt extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiensemester_kurzbz = isset($params['studiensemester_kurzbz']) ? $params['studiensemester_kurzbz'] : null;
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getDatumAbschlusspruefungFehlt($studiensemester_kurzbz, $studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array(
+						'prestudent_id' => $prestudent->prestudent_id,
+						'abschlusspruefung_id' => $prestudent->abschlusspruefung_id
+					),
+					'resolution_params' => array('abschlusspruefung_id' => $prestudent->abschlusspruefung_id)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/DatumSponsionFehlt.php b/application/libraries/issues/plausichecks/DatumSponsionFehlt.php
new file mode 100644
index 000000000..102a89656
--- /dev/null
+++ b/application/libraries/issues/plausichecks/DatumSponsionFehlt.php
@@ -0,0 +1,47 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class DatumSponsionFehlt extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiensemester_kurzbz = isset($params['studiensemester_kurzbz']) ? $params['studiensemester_kurzbz'] : null;
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getDatumSponsionFehlt($studiensemester_kurzbz, $studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array(
+						'prestudent_id' => $prestudent->prestudent_id,
+						'abschlusspruefung_id' => $prestudent->abschlusspruefung_id
+					),
+					'resolution_params' =>  array('abschlusspruefung_id' => $prestudent->abschlusspruefung_id)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/DatumStudiensemesterFalscheReihenfolge.php b/application/libraries/issues/plausichecks/DatumStudiensemesterFalscheReihenfolge.php
new file mode 100644
index 000000000..ab8566e47
--- /dev/null
+++ b/application/libraries/issues/plausichecks/DatumStudiensemesterFalscheReihenfolge.php
@@ -0,0 +1,45 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class DatumStudiensemesterFalscheReihenfolge extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getDatumStudiensemesterFalscheReihenfolge($studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array('prestudent_id' => $prestudent->prestudent_id),
+					'resolution_params' => array(
+						'prestudent_id' => $prestudent->prestudent_id
+					)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/FalscheAnzahlAbschlusspruefungen.php b/application/libraries/issues/plausichecks/FalscheAnzahlAbschlusspruefungen.php
new file mode 100644
index 000000000..7fbe2d828
--- /dev/null
+++ b/application/libraries/issues/plausichecks/FalscheAnzahlAbschlusspruefungen.php
@@ -0,0 +1,44 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class FalscheAnzahlAbschlusspruefungen extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiensemester_kurzbz = isset($params['studiensemester_kurzbz']) ? $params['studiensemester_kurzbz'] : null;
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getFalscheAnzahlAbschlusspruefungen($studiensemester_kurzbz, $studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array('prestudent_id' => $prestudent->prestudent_id),
+					'resolution_params' => array('prestudent_id' => $prestudent->prestudent_id)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/FalscheAnzahlHeimatadressen.php b/application/libraries/issues/plausichecks/FalscheAnzahlHeimatadressen.php
new file mode 100644
index 000000000..eac50a88a
--- /dev/null
+++ b/application/libraries/issues/plausichecks/FalscheAnzahlHeimatadressen.php
@@ -0,0 +1,42 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class FalscheAnzahlHeimatadressen extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiensemester_kurzbz = isset($params['studiensemester_kurzbz']) ? $params['studiensemester_kurzbz'] : null;
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$personRes = $this->_ci->plausichecklib->getFalscheAnzahlHeimatadressen($studiensemester_kurzbz, $studiengang_kz);
+
+		if (isError($personRes)) return $personRes;
+
+		if (hasData($personRes))
+		{
+			$persons = getData($personRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($persons as $person)
+			{
+				$results[] = array(
+					'person_id' => $person->person_id,
+					'resolution_params' => array('person_id' => $person->person_id)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/FalscheAnzahlZustelladressen.php b/application/libraries/issues/plausichecks/FalscheAnzahlZustelladressen.php
new file mode 100644
index 000000000..e2fc4a781
--- /dev/null
+++ b/application/libraries/issues/plausichecks/FalscheAnzahlZustelladressen.php
@@ -0,0 +1,42 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class FalscheAnzahlZustelladressen extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiensemester_kurzbz = isset($params['studiensemester_kurzbz']) ? $params['studiensemester_kurzbz'] : null;
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$personRes = $this->_ci->plausichecklib->getFalscheAnzahlZustelladressen($studiensemester_kurzbz, $studiengang_kz);
+
+		if (isError($personRes)) return $personRes;
+
+		if (hasData($personRes))
+		{
+			$persons = getData($personRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($persons as $person)
+			{
+				$results[] = array(
+					'person_id' => $person->person_id,
+					'resolution_params' => array('person_id' => $person->person_id)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/GbDatumWeitZurueck.php b/application/libraries/issues/plausichecks/GbDatumWeitZurueck.php
new file mode 100644
index 000000000..7a7cf0d6f
--- /dev/null
+++ b/application/libraries/issues/plausichecks/GbDatumWeitZurueck.php
@@ -0,0 +1,42 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class GbDatumWeitZurueck extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiensemester_kurzbz = isset($params['studiensemester_kurzbz']) ? $params['studiensemester_kurzbz'] : null;
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$personRes = $this->_ci->plausichecklib->getGbDatumWeitZurueck($studiensemester_kurzbz, $studiengang_kz);
+
+		if (isError($personRes)) return $personRes;
+
+		if (hasData($personRes))
+		{
+			$persons = getData($personRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($persons as $person)
+			{
+				$results[] = array(
+					'person_id' => $person->person_id,
+					'resolution_params' => array('person_id' => $person->person_id)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/InaktiverStudentAktiverStatus.php b/application/libraries/issues/plausichecks/InaktiverStudentAktiverStatus.php
new file mode 100644
index 000000000..76fd477e3
--- /dev/null
+++ b/application/libraries/issues/plausichecks/InaktiverStudentAktiverStatus.php
@@ -0,0 +1,47 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class InaktiverStudentAktiverStatus extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiensemester_kurzbz = isset($params['studiensemester_kurzbz']) ? $params['studiensemester_kurzbz'] : null;
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getInaktiverStudentAktiverStatus($studiensemester_kurzbz, $studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array('prestudent_id' => $prestudent->prestudent_id),
+					'resolution_params' => array(
+						'prestudent_id' => $prestudent->prestudent_id,
+						'studiensemester_kurzbz' => $studiensemester_kurzbz
+					)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/IncomingHeimatNationOesterreich.php b/application/libraries/issues/plausichecks/IncomingHeimatNationOesterreich.php
new file mode 100644
index 000000000..51726d969
--- /dev/null
+++ b/application/libraries/issues/plausichecks/IncomingHeimatNationOesterreich.php
@@ -0,0 +1,42 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class IncomingHeimatNationOesterreich extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiensemester_kurzbz = isset($params['studiensemester_kurzbz']) ? $params['studiensemester_kurzbz'] : null;
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$personRes = $this->_ci->plausichecklib->getIncomingHeimatNationOesterreich($studiensemester_kurzbz, $studiengang_kz);
+
+		if (isError($personRes)) return $personRes;
+
+		if (hasData($personRes))
+		{
+			$persons = getData($personRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($persons as $person)
+			{
+				$results[] = array(
+					'person_id' => $person->person_id,
+					'resolution_params' => array('person_id' => $person->person_id, 'studiensemester_kurzbz' => $studiensemester_kurzbz)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/IncomingOhneIoDatensatz.php b/application/libraries/issues/plausichecks/IncomingOhneIoDatensatz.php
new file mode 100644
index 000000000..9681554e5
--- /dev/null
+++ b/application/libraries/issues/plausichecks/IncomingOhneIoDatensatz.php
@@ -0,0 +1,43 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class IncomingOhneIoDatensatz extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getIncomingOhneIoDatensatz($studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array('prestudent_id' => $prestudent->prestudent_id),
+					'resolution_params' => array('prestudent_id' => $prestudent->prestudent_id)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/IncomingOrGsFoerderrelevant.php b/application/libraries/issues/plausichecks/IncomingOrGsFoerderrelevant.php
new file mode 100644
index 000000000..0e12ccac8
--- /dev/null
+++ b/application/libraries/issues/plausichecks/IncomingOrGsFoerderrelevant.php
@@ -0,0 +1,44 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class IncomingOrGsFoerderrelevant extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiensemester_kurzbz = isset($params['studiensemester_kurzbz']) ? $params['studiensemester_kurzbz'] : null;
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getIncomingOrGsFoerderrelevant($studiensemester_kurzbz, $studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array('prestudent_id' => $prestudent->prestudent_id),
+					'resolution_params' => array('prestudent_id' => $prestudent->prestudent_id)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/InskriptionVorLetzerBismeldung.php b/application/libraries/issues/plausichecks/InskriptionVorLetzerBismeldung.php
new file mode 100644
index 000000000..672dfa585
--- /dev/null
+++ b/application/libraries/issues/plausichecks/InskriptionVorLetzerBismeldung.php
@@ -0,0 +1,51 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class InskriptionVorLetzerBismeldung extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiensemester_kurzbz = isset($params['studiensemester_kurzbz']) ? $params['studiensemester_kurzbz'] : null;
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getInskriptionVorLetzerBismeldung($studiensemester_kurzbz, $studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array(
+						'datum_bismeldung' => date_format(date_create($prestudent->datum_bismeldung), 'd.m.Y'),
+						'prestudent_id' => $prestudent->prestudent_id,
+						'studiensemester_kurzbz' => $prestudent->studiensemester_kurzbz
+					),
+					'resolution_params' => array(
+						'prestudent_id' => $prestudent->prestudent_id,
+						'studiensemester_kurzbz' => $prestudent->studiensemester_kurzbz
+					)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/NationNichtOesterreichAberGemeinde.php b/application/libraries/issues/plausichecks/NationNichtOesterreichAberGemeinde.php
new file mode 100644
index 000000000..c61531e46
--- /dev/null
+++ b/application/libraries/issues/plausichecks/NationNichtOesterreichAberGemeinde.php
@@ -0,0 +1,42 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class NationNichtOesterreichAberGemeinde extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$personRes = $this->_ci->plausichecklib->getNationNichtOesterreichAberGemeinde($studiengang_kz);
+
+		if (isError($personRes)) return $personRes;
+
+		if (hasData($personRes))
+		{
+			$persons = getData($personRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($persons as $person)
+			{
+				$results[] = array(
+					'person_id' => $person->person_id,
+					'fehlertext_params' => array('gemeinde' => $person->gemeinde, 'adresse_id' => $person->adresse_id),
+					'resolution_params' => array('adresse_id' => $person->adresse_id)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/OrgformStgUngleichOrgformPrestudent.php b/application/libraries/issues/plausichecks/OrgformStgUngleichOrgformPrestudent.php
new file mode 100644
index 000000000..b7ef64c41
--- /dev/null
+++ b/application/libraries/issues/plausichecks/OrgformStgUngleichOrgformPrestudent.php
@@ -0,0 +1,52 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class OrgformStgUngleichOrgformPrestudent extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiensemester_kurzbz = isset($params['studiensemester_kurzbz']) ? $params['studiensemester_kurzbz'] : null;
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getOrgformStgUngleichOrgformPrestudent($studiensemester_kurzbz, $studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array(
+						'student_studiengang' => $prestudent->student_studiengang,
+						'student_orgform' => $prestudent->student_orgform,
+						'prestudent_id' => $prestudent->prestudent_id,
+						'studiensemester_kurzbz' => $prestudent->studiensemester_kurzbz
+					),
+					'resolution_params' => array(
+						'prestudent_id' => $prestudent->prestudent_id,
+						'studiensemester_kurzbz' => $prestudent->studiensemester_kurzbz
+					)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/PlausiChecker.php b/application/libraries/issues/plausichecks/PlausiChecker.php
new file mode 100644
index 000000000..bfa72b5e0
--- /dev/null
+++ b/application/libraries/issues/plausichecks/PlausiChecker.php
@@ -0,0 +1,24 @@
+<?php
+
+/**
+ * class defining ressources and method to use for plausicheck issue producer
+ */
+abstract class PlausiChecker
+{
+	protected $_ci; // code igniter instance
+
+	public function __construct()
+	{
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		// load libraries
+		$this->_ci->load->library('issues/PlausicheckLib'); // load plausicheck library
+	}
+
+	/**
+	 * Executes a plausi check.
+	 * @param $paramsForChecking array parameters needed for executing the check
+	 * @return array with objects which failed the plausi check
+	 */
+	abstract public function executePlausiCheck($paramsForChecking);
+}
diff --git a/application/libraries/issues/plausichecks/PrestudentMischformOhneOrgform.php b/application/libraries/issues/plausichecks/PrestudentMischformOhneOrgform.php
new file mode 100644
index 000000000..369085089
--- /dev/null
+++ b/application/libraries/issues/plausichecks/PrestudentMischformOhneOrgform.php
@@ -0,0 +1,50 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class PrestudentMischformOhneOrgform extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiensemester_kurzbz = isset($params['studiensemester_kurzbz']) ? $params['studiensemester_kurzbz'] : null;
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getPrestudentMischformOhneOrgform($studiensemester_kurzbz, $studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array(
+						'prestudent_id' => $prestudent->prestudent_id,
+						'studiensemester_kurzbz' => $prestudent->studiensemester_kurzbz
+					),
+					'resolution_params' => array(
+						'prestudent_id' => $prestudent->prestudent_id,
+						'studiensemester_kurzbz' => $prestudent->studiensemester_kurzbz
+					)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/StgPrestudentUngleichStgStudent.php b/application/libraries/issues/plausichecks/StgPrestudentUngleichStgStudent.php
new file mode 100644
index 000000000..4eb25ed11
--- /dev/null
+++ b/application/libraries/issues/plausichecks/StgPrestudentUngleichStgStudent.php
@@ -0,0 +1,43 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class StgPrestudentUngleichStgStudent extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getStgPrestudentUngleichStgStudent($studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array('prestudent_id' => $prestudent->prestudent_id),
+					'resolution_params' => array('prestudent_id' => $prestudent->prestudent_id)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/StgPrestudentUngleichStgStudienplan.php b/application/libraries/issues/plausichecks/StgPrestudentUngleichStgStudienplan.php
new file mode 100644
index 000000000..7175725fd
--- /dev/null
+++ b/application/libraries/issues/plausichecks/StgPrestudentUngleichStgStudienplan.php
@@ -0,0 +1,43 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class StgPrestudentUngleichStgStudienplan extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getStgPrestudentUngleichStgStudienplan($studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array('prestudent_id' => $prestudent->prestudent_id, 'studienplan' => $prestudent->studienplan),
+					'resolution_params' => array('prestudent_id' => $prestudent->prestudent_id, 'studienordnung_id' => $prestudent->studienordnung_id)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/StudentstatusNachAbbrecher.php b/application/libraries/issues/plausichecks/StudentstatusNachAbbrecher.php
new file mode 100644
index 000000000..12a7516ef
--- /dev/null
+++ b/application/libraries/issues/plausichecks/StudentstatusNachAbbrecher.php
@@ -0,0 +1,43 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class StudentstatusNachAbbrecher extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getStudentstatusNachAbbrecher($studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array('prestudent_id' => $prestudent->prestudent_id),
+					'resolution_params' => array('prestudent_id' => $prestudent->prestudent_id)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/plausichecks/StudienplanUngueltig.php b/application/libraries/issues/plausichecks/StudienplanUngueltig.php
new file mode 100644
index 000000000..6b8fe49aa
--- /dev/null
+++ b/application/libraries/issues/plausichecks/StudienplanUngueltig.php
@@ -0,0 +1,51 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+require_once('PlausiChecker.php');
+
+/**
+ *
+ */
+class StudienplanUngueltig extends PlausiChecker
+{
+	public function executePlausiCheck($params)
+	{
+		$results = array();
+
+		// pass parameters needed for plausicheck
+		$studiensemester_kurzbz = isset($params['studiensemester_kurzbz']) ? $params['studiensemester_kurzbz'] : null;
+		$studiengang_kz = isset($params['studiengang_kz']) ? $params['studiengang_kz'] : null;
+
+		// get all students failing the plausicheck
+		$prestudentRes = $this->_ci->plausichecklib->getStudienplanUngueltig($studiensemester_kurzbz, $studiengang_kz);
+
+		if (isError($prestudentRes)) return $prestudentRes;
+
+		if (hasData($prestudentRes))
+		{
+			$prestudents = getData($prestudentRes);
+
+			// populate results with data necessary for writing issues
+			foreach ($prestudents as $prestudent)
+			{
+				$results[] = array(
+					'person_id' => $prestudent->person_id,
+					'oe_kurzbz' => $prestudent->prestudent_stg_oe_kurzbz,
+					'fehlertext_params' => array(
+						'studienplan' => $prestudent->studienplan,
+						'ausbildungssemester' => $prestudent->ausbildungssemester,
+						'prestudent_id' => $prestudent->prestudent_id
+					),
+					'resolution_params' => array(
+						'prestudent_id' => $prestudent->prestudent_id,
+						'studiensemester_kurzbz' => $prestudent->studiensemester_kurzbz
+					)
+				);
+			}
+		}
+
+		// return the results
+		return success($results);
+	}
+}
diff --git a/application/libraries/issues/CORE_INOUT_0001.php b/application/libraries/issues/resolvers/CORE_INOUT_0001.php
similarity index 100%
rename from application/libraries/issues/CORE_INOUT_0001.php
rename to application/libraries/issues/resolvers/CORE_INOUT_0001.php
diff --git a/application/libraries/issues/CORE_INOUT_0002.php b/application/libraries/issues/resolvers/CORE_INOUT_0002.php
similarity index 100%
rename from application/libraries/issues/CORE_INOUT_0002.php
rename to application/libraries/issues/resolvers/CORE_INOUT_0002.php
diff --git a/application/libraries/issues/CORE_INOUT_0003.php b/application/libraries/issues/resolvers/CORE_INOUT_0003.php
similarity index 100%
rename from application/libraries/issues/CORE_INOUT_0003.php
rename to application/libraries/issues/resolvers/CORE_INOUT_0003.php
diff --git a/application/libraries/issues/CORE_INOUT_0004.php b/application/libraries/issues/resolvers/CORE_INOUT_0004.php
similarity index 100%
rename from application/libraries/issues/CORE_INOUT_0004.php
rename to application/libraries/issues/resolvers/CORE_INOUT_0004.php
diff --git a/application/libraries/issues/CORE_INOUT_0005.php b/application/libraries/issues/resolvers/CORE_INOUT_0005.php
similarity index 100%
rename from application/libraries/issues/CORE_INOUT_0005.php
rename to application/libraries/issues/resolvers/CORE_INOUT_0005.php
diff --git a/application/libraries/issues/CORE_INOUT_0006.php b/application/libraries/issues/resolvers/CORE_INOUT_0006.php
similarity index 93%
rename from application/libraries/issues/CORE_INOUT_0006.php
rename to application/libraries/issues/resolvers/CORE_INOUT_0006.php
index a447a9625..6894c9878 100644
--- a/application/libraries/issues/CORE_INOUT_0006.php
+++ b/application/libraries/issues/resolvers/CORE_INOUT_0006.php
@@ -15,7 +15,6 @@ class CORE_INOUT_0006 implements IIssueResolvedChecker
 		$this->_ci =& get_instance(); // get code igniter instance
 
 		$this->_ci->load->model('codex/Bisio_model', 'BisioModel');
-		//$this->_ci->load->model('codex/Aufenthaltfoerderung_model', 'AufenthaltfoerderungModel');
 
 		// get all Zwecke
 		$this->_ci->BisioModel->addSelect('ects_erworben');
diff --git a/application/libraries/issues/resolvers/CORE_INOUT_0007.php b/application/libraries/issues/resolvers/CORE_INOUT_0007.php
new file mode 100644
index 000000000..2d9c7a3f4
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_INOUT_0007.php
@@ -0,0 +1,32 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_INOUT_0007 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['issue_person_id']) || !is_numeric($params['issue_person_id']))
+			return error('Person Id missing, issue_id: '.$params['issue_id']);
+
+		if (!isset($params['studiensemester_kurzbz']) || isEmptyString($params['studiensemester_kurzbz']))
+			return error('Studiensemester missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getIncomingHeimatNationOesterreich($params['studiensemester_kurzbz'], null, $params['issue_person_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_INOUT_0008.php b/application/libraries/issues/resolvers/CORE_INOUT_0008.php
new file mode 100644
index 000000000..afa43893a
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_INOUT_0008.php
@@ -0,0 +1,29 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_INOUT_0008 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['prestudent_id']) || !is_numeric($params['prestudent_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getIncomingOhneIoDatensatz(null, $params['prestudent_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_INOUT_0009.php b/application/libraries/issues/resolvers/CORE_INOUT_0009.php
new file mode 100644
index 000000000..b56344042
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_INOUT_0009.php
@@ -0,0 +1,29 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming or external GS student should not be foerderrelevant.
+ */
+class CORE_INOUT_0009 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['prestudent_id']) || !is_numeric($params['prestudent_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getIncomingOrGsFoerderrelevant(null, null, $params['prestudent_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_PERSON_0001.php b/application/libraries/issues/resolvers/CORE_PERSON_0001.php
new file mode 100644
index 000000000..bd94fea59
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_PERSON_0001.php
@@ -0,0 +1,29 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_PERSON_0001 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['issue_person_id']) || !is_numeric($params['issue_person_id']))
+			return error('Person Id missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getGbDatumWeitZurueck(null, null, $params['issue_person_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_PERSON_0002.php b/application/libraries/issues/resolvers/CORE_PERSON_0002.php
new file mode 100644
index 000000000..d1bb2fe94
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_PERSON_0002.php
@@ -0,0 +1,29 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_PERSON_0002 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['issue_person_id']) || !is_numeric($params['issue_person_id']))
+			return error('Person Id missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getNationNichtOesterreichAberGemeinde(null, $params['issue_person_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_PERSON_0003.php b/application/libraries/issues/resolvers/CORE_PERSON_0003.php
new file mode 100644
index 000000000..08fea6c05
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_PERSON_0003.php
@@ -0,0 +1,29 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_PERSON_0003 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['issue_person_id']) || !is_numeric($params['issue_person_id']))
+			return error('Person Id missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getFalscheAnzahlHeimatadressen(null, null, $params['issue_person_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_PERSON_0004.php b/application/libraries/issues/resolvers/CORE_PERSON_0004.php
new file mode 100644
index 000000000..bfe243fd1
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_PERSON_0004.php
@@ -0,0 +1,29 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_PERSON_0004 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['issue_person_id']) || !is_numeric($params['issue_person_id']))
+			return error('Person Id missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getFalscheAnzahlZustelladressen(null, null, $params['issue_person_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_STG_0001.php b/application/libraries/issues/resolvers/CORE_STG_0001.php
new file mode 100644
index 000000000..97cef6056
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_STG_0001.php
@@ -0,0 +1,29 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_STG_0001 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['prestudent_id']) || !is_numeric($params['prestudent_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getStgPrestudentUngleichStgStudent(null, $params['prestudent_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_STG_0002.php b/application/libraries/issues/resolvers/CORE_STG_0002.php
new file mode 100644
index 000000000..fe414de38
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_STG_0002.php
@@ -0,0 +1,32 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_STG_0002 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['prestudent_id']) || !is_numeric($params['prestudent_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		if (!isset($params['studiensemester_kurzbz']) || isEmptyString($params['studiensemester_kurzbz']))
+			return error('Studiensemester missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getOrgformStgUngleichOrgformPrestudent($params['studiensemester_kurzbz'], null, $params['prestudent_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_STG_0003.php b/application/libraries/issues/resolvers/CORE_STG_0003.php
new file mode 100644
index 000000000..33cb0846b
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_STG_0003.php
@@ -0,0 +1,32 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_STG_0003 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['prestudent_id']) || !is_numeric($params['prestudent_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		if (!isset($params['studiensemester_kurzbz']) || isEmptyString($params['studiensemester_kurzbz']))
+			return error('Studiensemester missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getPrestudentMischformOhneOrgform($params['studiensemester_kurzbz'], null, $params['prestudent_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_STG_0004.php b/application/libraries/issues/resolvers/CORE_STG_0004.php
new file mode 100644
index 000000000..02d45bbd3
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_STG_0004.php
@@ -0,0 +1,32 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_STG_0004 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['prestudent_id']) || !is_numeric($params['prestudent_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		if (!isset($params['studienordnung_id']) || !is_numeric($params['studienordnung_id']))
+			return error('Studienordnung Id missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getStgPrestudentUngleichStgStudienplan(null, $params['prestudent_id'], $params['studienordnung_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0001.php b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0001.php
new file mode 100644
index 000000000..78c49810b
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0001.php
@@ -0,0 +1,29 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_STUDENTSTATUS_0001 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['prestudent_id']) || !is_numeric($params['prestudent_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getAbbrecherAktiv(null, $params['prestudent_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0002.php b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0002.php
new file mode 100644
index 000000000..23943397a
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0002.php
@@ -0,0 +1,29 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_STUDENTSTATUS_0002 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['prestudent_id']) || !is_numeric($params['prestudent_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getStudentstatusNachAbbrecher(null, $params['prestudent_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0003.php b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0003.php
new file mode 100644
index 000000000..6ac243b4f
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0003.php
@@ -0,0 +1,32 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_STUDENTSTATUS_0003 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['prestudent_id']) || !is_numeric($params['prestudent_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		if (!isset($params['studiensemester_kurzbz']) || isEmptyString($params['studiensemester_kurzbz']))
+			return error('Studiensemester missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getAusbildungssemPrestudentUngleichAusbildungssemStatus($params['studiensemester_kurzbz'], null, $params['prestudent_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0004.php b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0004.php
new file mode 100644
index 000000000..d76215b6a
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0004.php
@@ -0,0 +1,32 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_STUDENTSTATUS_0004 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['prestudent_id']) || !is_numeric($params['prestudent_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		if (!isset($params['studiensemester_kurzbz']) || isEmptyString($params['studiensemester_kurzbz']))
+			return error('Studiensemester missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getInaktiverStudentAktiverStatus($params['studiensemester_kurzbz'], null, $params['prestudent_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0005.php b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0005.php
new file mode 100644
index 000000000..7f7ca4723
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0005.php
@@ -0,0 +1,32 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_STUDENTSTATUS_0005 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['prestudent_id']) || !is_numeric($params['prestudent_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		if (!isset($params['studiensemester_kurzbz']) || isEmptyString($params['studiensemester_kurzbz']))
+			return error('Studiensemester missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getInskriptionVorLetzerBismeldung($params['studiensemester_kurzbz'], null, $params['prestudent_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0006.php b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0006.php
new file mode 100644
index 000000000..ba1e5b715
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0006.php
@@ -0,0 +1,29 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_STUDENTSTATUS_0006 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['prestudent_id']) || !is_numeric($params['prestudent_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getDatumStudiensemesterFalscheReihenfolge(null, $params['prestudent_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0007.php b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0007.php
new file mode 100644
index 000000000..1dd8fdcb2
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0007.php
@@ -0,0 +1,29 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_STUDENTSTATUS_0007 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['prestudent_id']) || !is_numeric($params['prestudent_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getAktiverStudentOhneStatus(null, $params['prestudent_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0008.php b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0008.php
new file mode 100644
index 000000000..83357d9bf
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0008.php
@@ -0,0 +1,32 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_STUDENTSTATUS_0008 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['prestudent_id']) || !is_numeric($params['prestudent_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		if (!isset($params['studiensemester_kurzbz']) || isEmptyString($params['studiensemester_kurzbz']))
+			return error('Studiensemester missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getStudienplanUngueltig($params['studiensemester_kurzbz'], null, $params['prestudent_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0009.php b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0009.php
new file mode 100644
index 000000000..b1b5e9876
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0009.php
@@ -0,0 +1,29 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_STUDENTSTATUS_0009 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['prestudent_id']) || !is_numeric($params['prestudent_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getFalscheAnzahlAbschlusspruefungen(null, null, $params['prestudent_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0010.php b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0010.php
new file mode 100644
index 000000000..1e3a6849b
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0010.php
@@ -0,0 +1,29 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_STUDENTSTATUS_0010 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['abschlusspruefung_id']) || !is_numeric($params['abschlusspruefung_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getDatumAbschlusspruefungFehlt(null, null, $params['abschlusspruefung_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0011.php b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0011.php
new file mode 100644
index 000000000..233240305
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0011.php
@@ -0,0 +1,29 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_STUDENTSTATUS_0011 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['abschlusspruefung_id']) || !is_numeric($params['abschlusspruefung_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getDatumSponsionFehlt(null, null, $params['abschlusspruefung_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0012.php b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0012.php
new file mode 100644
index 000000000..38832edc0
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0012.php
@@ -0,0 +1,32 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_STUDENTSTATUS_0012 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['prestudent_id']) || !is_numeric($params['prestudent_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		if (!isset($params['studiensemester_kurzbz']) || isEmptyString($params['studiensemester_kurzbz']))
+			return error('Studiensemester missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getBewerberNichtZumRtAngetreten($params['studiensemester_kurzbz'], null, $params['prestudent_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0013.php b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0013.php
new file mode 100644
index 000000000..78ad40a8e
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0013.php
@@ -0,0 +1,32 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_STUDENTSTATUS_0013 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['prestudent_id']) || !is_numeric($params['prestudent_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		if (!isset($params['studiensemester_kurzbz']) || isEmptyString($params['studiensemester_kurzbz']))
+			return error('Studiensemester missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getAktSemesterNull($params['studiensemester_kurzbz'], null, $params['prestudent_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0014.php b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0014.php
new file mode 100644
index 000000000..8d96b7c65
--- /dev/null
+++ b/application/libraries/issues/resolvers/CORE_STUDENTSTATUS_0014.php
@@ -0,0 +1,29 @@
+<?php
+
+if (! defined('BASEPATH')) exit('No direct script access allowed');
+
+/**
+ * Incoming shouldn't have austrian home address.
+ */
+class CORE_STUDENTSTATUS_0014 implements IIssueResolvedChecker
+{
+	public function checkIfIssueIsResolved($params)
+	{
+		if (!isset($params['prestudent_id']) || !is_numeric($params['prestudent_id']))
+			return error('Prestudent Id missing, issue_id: '.$params['issue_id']);
+
+		$this->_ci =& get_instance(); // get code igniter instance
+
+		$this->_ci->load->library('issues/PlausicheckLib');
+
+		// check if issue persists
+		$checkRes = $this->_ci->plausichecklib->getAbschlussstatusFehlt(null, null, $params['prestudent_id']);
+
+		if (isError($checkRes)) return $checkRes;
+
+		if (hasData($checkRes))
+			return success(false); // not resolved if issue is still present
+		else
+			return success(true); // resolved otherwise
+	}
+}
diff --git a/application/libraries/issues/CORE_ZGV_0001.php b/application/libraries/issues/resolvers/CORE_ZGV_0001.php
similarity index 100%
rename from application/libraries/issues/CORE_ZGV_0001.php
rename to application/libraries/issues/resolvers/CORE_ZGV_0001.php
diff --git a/application/libraries/issues/CORE_ZGV_0002.php b/application/libraries/issues/resolvers/CORE_ZGV_0002.php
similarity index 100%
rename from application/libraries/issues/CORE_ZGV_0002.php
rename to application/libraries/issues/resolvers/CORE_ZGV_0002.php
diff --git a/application/libraries/issues/CORE_ZGV_0003.php b/application/libraries/issues/resolvers/CORE_ZGV_0003.php
similarity index 100%
rename from application/libraries/issues/CORE_ZGV_0003.php
rename to application/libraries/issues/resolvers/CORE_ZGV_0003.php
diff --git a/application/libraries/issues/CORE_ZGV_0004.php b/application/libraries/issues/resolvers/CORE_ZGV_0004.php
similarity index 100%
rename from application/libraries/issues/CORE_ZGV_0004.php
rename to application/libraries/issues/resolvers/CORE_ZGV_0004.php
diff --git a/application/libraries/issues/CORE_ZGV_0005.php b/application/libraries/issues/resolvers/CORE_ZGV_0005.php
similarity index 100%
rename from application/libraries/issues/CORE_ZGV_0005.php
rename to application/libraries/issues/resolvers/CORE_ZGV_0005.php
diff --git a/application/views/system/issues/issuesData.php b/application/views/system/issues/issuesData.php
index 418f0ead1..50b7c1483 100644
--- a/application/views/system/issues/issuesData.php
+++ b/application/views/system/issues/issuesData.php
@@ -132,16 +132,17 @@ if (!isEmptyArray($all_oe_kurzbz_berechtigt))
 				)";
 }
 
-$query .= " ORDER BY CASE
-				WHEN iss.status_kurzbz = '".IssuesLib::STATUS_NEU."' THEN 0
-				WHEN iss.status_kurzbz = '".IssuesLib::STATUS_IN_BEARBEITUNG."' THEN 1
-				ELSE 2
-			END,
+$query .= " ORDER BY
 			CASE
 				WHEN fehlertyp_kurzbz = '".IssuesLib::ERRORTYPE_CODE."' THEN 0
 				WHEN fehlertyp_kurzbz = '".IssuesLib::WARNINGTYPE_CODE."' THEN 1
 				ELSE 2
 			END,
+			CASE
+				WHEN iss.status_kurzbz = '".IssuesLib::STATUS_NEU."' THEN 0
+				WHEN iss.status_kurzbz = '".IssuesLib::STATUS_IN_BEARBEITUNG."' THEN 1
+				ELSE 2
+			END,
 			datum DESC, fehlercode, issue_id DESC";
 
 $filterWidgetArray = array(
diff --git a/application/views/system/issues/plausichecks.php b/application/views/system/issues/plausichecks.php
new file mode 100644
index 000000000..4016e64cd
--- /dev/null
+++ b/application/views/system/issues/plausichecks.php
@@ -0,0 +1,101 @@
+<?php
+$this->load->view(
+	'templates/FHC-Header',
+	array(
+		'title' => 'Plausichecks',
+		'jquery3' => true,
+		'jqueryui1' => true,
+		'jquerycheckboxes' => true,
+		'bootstrap3' => true,
+		'fontawesome4' => true,
+		'sbadmintemplate3' => true,
+		'ajaxlib' => true,
+		'navigationwidget' => true,
+		'dialoglib' => true,
+		'customCSSs' => array('public/css/sbadmin2/admintemplate_contentonly.css'),
+		'customJSs' => array('public/js/issues/plausichecks.js')
+	)
+);
+?>
+
+<div id="wrapper">
+
+	<?php echo $this->widgetlib->widget('NavigationWidget'); ?>
+
+	<div id="page-wrapper">
+		<div class="container-fluid">
+			<div class="row">
+				<div class="col-lg-12">
+					<h3 class="page-header">
+						Plausichecks
+					</h3>
+				</div>
+			</div>
+			<div class="row">
+				<div class="col-xs-2 form-group">
+					<label>Studiensemester</label>
+					<select class="form-control" name="studiensemester" id="studiensemester">
+						<?php
+						foreach ($semester as $sem):
+							$selected = $sem->studiensemester_kurzbz === $currsemester[0]->studiensemester_kurzbz ? ' selected=""' : '';
+							?>
+							<option value="<?php echo $sem->studiensemester_kurzbz ?>"<?php echo $selected ?>>
+								<?php echo $sem->studiensemester_kurzbz ?>
+							</option>
+						<?php endforeach; ?>
+					</select>
+				</div>
+				<div class="col-xs-4 form-group">
+					<label>Studiengang</label>
+					<select class="form-control" name="studiengang_kz" id="studiengang_kz">
+						<option value="" selected="selected">Alle</option>';
+						<?php
+						$typ = '';
+						foreach ($studiengaenge as $studiengang):
+							if ($typ != $studiengang->typ || $typ == '')
+							{
+								if ($typ != '')
+									echo '</optgroup>';
+
+								echo '<optgroup label = "'.($studiengang->typbezeichnung !== '' ? $studiengang->typbezeichnung : $studiengang).'">';
+							}
+							$typ = $studiengang->typ;
+							?>
+							<option value="<?php echo $studiengang->studiengang_kz ?>">
+								<?php echo $studiengang->kuerzel . ' - ' . $studiengang->bezeichnung ?>
+							</option>
+						<?php endforeach; ?>
+					</select>
+				</div>
+				<div class="col-xs-3 col-lg-4 form-group">
+					<label>Fehler</label>
+					<select class="form-control" name="fehler_kurzbz" id="fehler_kurzbz">
+						<option value="" selected="selected">Alle</option>';
+						<?php foreach ($fehler as $fehler_kurzbz):?>
+							<option value="<?php echo $fehler_kurzbz ?>">
+								<?php echo $fehler_kurzbz ?>
+							</option>
+						<?php endforeach; ?>
+					</select>
+				</div>
+				<div class="col-xs-3 col-lg-2 form-group text-right">
+					<label>&nbsp;</label>
+					<br />
+					<button class="btn btn-default" id="plausistart">Checks starten</button>
+				</div>
+			</div>
+			<div class="row">
+				<div class="col-xs-12">
+					<div class="well well-sm wellminheight">
+						<h4 class="text-center">Output:</h4>
+						<div id="plausioutput" class="panel panel-body">
+							<div id="plausioutput-text">-</div>
+						</div>
+					</div>
+				</div>
+			</div>
+		</div>
+	</div>
+</div>
+
+<?php $this->load->view('templates/FHC-Footer'); ?>
diff --git a/public/js/issues/issuesDataset.js b/public/js/issues/issuesDataset.js
index 57a8fb4fd..5f2fba4ce 100644
--- a/public/js/issues/issuesDataset.js
+++ b/public/js/issues/issuesDataset.js
@@ -3,12 +3,13 @@
  */
 
 var IssuesDataset = {
+	// number of max issue ids that can be sent in one request for status change
+	maxIssuesPerRequest: 1000,
 
 	/**
 	 * adds person table additional actions html (above and beneath it)
 	 */
-	appendTableActionsHtml: function()
-	{
+	appendTableActionsHtml: function() {
 		let auswahlStatus =
 			'<div class="input-group">' +
 				'<select class="form-control d-inline auswahlStatus">' +
@@ -78,69 +79,74 @@ var IssuesDataset = {
 	/**
 	 * sets functionality for the actions above and beneath the person table
 	 */
-	setTableActions: function()
-	{
-		$(".setStatus").click(function()
+	setTableActions: function() {
+		$(".setStatus").click(function() {
+			let status_kurzbz = $(".auswahlStatus").val();
+			let issue_ids_sel = $("#filterTableDataset input:checked[name=issue_id\\[\\]]");
+
+			if(status_kurzbz.length <= 0)
+				return FHC_DialogLib.alertInfo(FHC_PhrasesLib.t("fehlermonitoring", "bitteStatusWaehlen"));
+
+			if(issue_ids_sel.length <= 0)
+				return FHC_DialogLib.alertInfo(FHC_PhrasesLib.t("fehlermonitoring", "bitteFehlerWaehlen"));
+
+			let issue_ids = [];
+
+			for (let i = 0; i < issue_ids_sel.length; i++)
 			{
-				let status_kurzbz = $(".auswahlStatus").val();
-				let issue_ids_sel = $("#filterTableDataset input:checked[name=issue_id\\[\\]]");
-
-				if(status_kurzbz.length <= 0)
-					return FHC_DialogLib.alertInfo(FHC_PhrasesLib.t("fehlermonitoring", "bitteStatusWaehlen"));
-
-				if(issue_ids_sel.length <= 0)
-					return FHC_DialogLib.alertInfo(FHC_PhrasesLib.t("fehlermonitoring", "bitteFehlerWaehlen"));
-
-				let issue_ids = [];
-
-				for (let i = 0; i < issue_ids_sel.length; i++)
-				{
-					issue_ids.push($(issue_ids_sel[i]).val());
-				}
-
-				FHC_AjaxClient.ajaxCallPost(
-					'system/issues/Issues/changeIssueStatus',
-					{
-						"issue_ids": issue_ids,
-						"status_kurzbz": status_kurzbz
-					},
-					{
-						successCallback: function(data, textStatus, jqXHR) {
-							if (FHC_AjaxClient.isError(data))
-							{
-								FHC_DialogLib.alertError(
-									FHC_PhrasesLib.t("fehlermonitoring", "statusAendernFehler") + ": "
-									+ FHC_AjaxClient.getError(data)
-								);
-							}
-							else if (FHC_AjaxClient.hasData(data))
-							{
-								FHC_FilterWidget.reloadDataset();
-								FHC_DialogLib.alertSuccess(FHC_AjaxClient.getData(data));
-							}
-							else
-								FHC_DialogLib.alertError(FHC_PhrasesLib.t("fehlermonitoring", "statusAendernUnbekannterFehler"));
-						},
-						errorCallback: function(jqXHR, textStatus, errorThrown) {
-							FHC_DialogLib.alertError(FHC_PhrasesLib.t("fehlermonitoring", "statusAendernFehler") + ": " + textStatus);
-						}
-					}
-				);
+				issue_ids.push($(issue_ids_sel[i]).val());
 			}
-		);
 
-		$(".selectAll").click(function()
-			{
-				//select only trs if not filtered by tablesorter
-				var trs = $("#filterTableDataset tbody tr").not(".filtered");
-				trs.find("input[name=issue_id\\[\\]]").prop("checked", true);
-			}
-		);
+			IssuesDataset.changeIssueStatus(issue_ids, status_kurzbz);
+		});
 
-		$(".unselectAll").click(function()
-			{
+		$(".selectAll").click(function() {
+			//select only trs if not filtered by tablesorter
+			var trs = $("#filterTableDataset tbody tr").not(".filtered");
+			trs.find("input[name=issue_id\\[\\]]").prop("checked", true);
+		});
+
+		$(".unselectAll").click(function() {
 				var trs = $("#filterTableDataset tbody tr").not(".filtered");
 				trs.find("input[name=issue_id\\[\\]]").prop("checked", false);
+		});
+	},
+	/**
+	 * sends request for changing issue status
+	 */
+	changeIssueStatus: function(issue_ids, status_kurzbz) {
+		FHC_AjaxClient.ajaxCallPost(
+			'system/issues/Issues/changeIssueStatus',
+			{
+				// split up issue ids if too much data for single request
+				"issue_ids": issue_ids.slice(0, IssuesDataset.maxIssuesPerRequest),
+				"status_kurzbz": status_kurzbz
+			},
+			{
+				successCallback: function(data, textStatus, jqXHR) {
+					if (FHC_AjaxClient.isError(data))
+					{
+						FHC_DialogLib.alertError(
+							FHC_PhrasesLib.t("fehlermonitoring", "statusAendernFehler") + ": "
+							+ FHC_AjaxClient.getError(data)
+						);
+					}
+					else if (FHC_AjaxClient.hasData(data))
+					{
+						if (issue_ids.length < IssuesDataset.maxIssuesPerRequest)
+						{
+							FHC_DialogLib.alertSuccess(FHC_AjaxClient.getData(data));
+							FHC_FilterWidget.reloadDataset();
+						}
+						else // send next chunk of data
+							IssuesDataset.changeIssueStatus(issue_ids.slice(IssuesDataset.maxIssuesPerRequest), status_kurzbz);
+					}
+					else
+						FHC_DialogLib.alertError(FHC_PhrasesLib.t("fehlermonitoring", "statusAendernUnbekannterFehler"));
+				},
+				errorCallback: function(jqXHR, textStatus, errorThrown) {
+					FHC_DialogLib.alertError(FHC_PhrasesLib.t("fehlermonitoring", "statusAendernFehler") + ": " + textStatus);
+				}
 			}
 		);
 	}
diff --git a/public/js/issues/plausichecks.js b/public/js/issues/plausichecks.js
new file mode 100644
index 000000000..f679c9434
--- /dev/null
+++ b/public/js/issues/plausichecks.js
@@ -0,0 +1,67 @@
+/**
+ * Javascript file for Plausichecks display
+ */
+
+var Plausichecks = {
+
+	startPlausichecks: function (studiensemester_kurzbz, studiengang_kz, fehler_kurzbz) {
+		FHC_AjaxClient.ajaxCallGet(
+			'system/issues/Plausichecks/runChecks',
+			{
+				studiensemester_kurzbz: studiensemester_kurzbz,
+				studiengang_kz: studiengang_kz,
+				fehler_kurzbz: fehler_kurzbz
+			},
+			{
+				successCallback: function (data, textStatus, jqXHR) {
+					if (FHC_AjaxClient.isError(data)) FHC_DialogLib.alertError(FHC_AjaxClient.getError(data));
+
+					let messageStr = "<strong>Plausichecks Prüfung Start</strong>";
+
+					if (FHC_AjaxClient.hasData(data))
+					{
+						let issueTexts = FHC_AjaxClient.getData(data);
+
+						for (let fehler_kurzbz in issueTexts)
+						{
+							messageStr += "<br /><br /><span>Prüfe " + fehler_kurzbz + "...</span>";
+							let texts = issueTexts[fehler_kurzbz];
+
+							if (texts.length == 0) {
+								messageStr += "<br /><span class='text-success'>Keine Issues für " + fehler_kurzbz + "</span>";
+								continue;
+							}
+
+							for (i = 0; i < texts.length; i++)
+							{
+								messageStr += "<br /><span class='text-danger'>" + texts[i] + "</span>";
+							}
+						}
+					}
+					messageStr += "<br /><br /><strong>Plausichecks Prüfung Ende</strong>";
+					$("#plausioutput").html(messageStr);
+				},
+				errorCallback: function (jqXHR, textStatus, errorThrown) {
+					FHC_DialogLib.alertError(textStatus);
+				}
+			}
+		);
+	},
+
+};
+
+/**
+ * When JQuery is up
+ */
+$(document).ready(function () {
+	// start the Plausicheck run on button click
+	$("#plausistart").click(
+		function () {
+			Plausichecks.startPlausichecks(
+				$("#studiensemester").val(),
+				$("#studiengang_kz").val(),
+				$("#fehler_kurzbz").val(),
+			);
+		}
+	)
+});
diff --git a/system/checkStudenten.php b/system/checkStudenten.php
index 2590574db..14c4f2239 100644
--- a/system/checkStudenten.php
+++ b/system/checkStudenten.php
@@ -492,7 +492,7 @@ if ($result = $db->db_query($qry))
 /*
  *	 Studierende im aktuellen StSem die in Mischformstudiengängen keine Orgform eingetragen haben
  */
-$text .= "<br><br>Suche alle Bewerber die keine Orgform eingetragen haben.<br><br>";
+$text .= "<br><br>Suche alle Studierenden die keine Orgform eingetragen haben.<br><br>";
 
 $qry = "
 SELECT
diff --git a/system/dbupdate_3.3.php b/system/dbupdate_3.3.php
index 3c016cc39..f57b9d172 100644
--- a/system/dbupdate_3.3.php
+++ b/system/dbupdate_3.3.php
@@ -6783,7 +6783,6 @@ if (!$result = @$db->db_query("SELECT aktiv FROM bis.tbl_zgvdoktor LIMIT 1"))
 		echo '<br>Spalte aktiv zu bis.tbl_zgvdoktor hinzugefügt';
 }
 
-
 // ADD COLUMN studienkennung_uni to bis.tbl_gsprogramm
 if(!@$db->db_query("SELECT studienkennung_uni FROM bis.tbl_gsprogramm LIMIT 1"))
 {
diff --git a/system/dbupdate_3.4.php b/system/dbupdate_3.4.php
index 57f037d14..821bbc5c6 100644
--- a/system/dbupdate_3.4.php
+++ b/system/dbupdate_3.4.php
@@ -30,6 +30,7 @@ require_once('dbupdate_3.4/example2.php');
 
 require_once('dbupdate_3.4/26173_index_webservicelog.php');
 require_once('dbupdate_3.4/24682_reihungstest_zugangscode_fuer_login.php');
+require_once('dbupdate_3.4/17512_fehlercode_constraints.php');
 
 // *** Pruefung und hinzufuegen der neuen Attribute und Tabellen
 echo '<H2>Pruefe Tabellen und Attribute!</H2>';
diff --git a/system/dbupdate_3.4/17512_fehlercode_constraints.php b/system/dbupdate_3.4/17512_fehlercode_constraints.php
new file mode 100644
index 000000000..91a3303b5
--- /dev/null
+++ b/system/dbupdate_3.4/17512_fehlercode_constraints.php
@@ -0,0 +1,54 @@
+<?php
+
+if (! defined('DB_NAME')) exit('No direct script access allowed');
+
+// Remove UNIQUE constraint on fehlercode and fehler_kurzbz on system.tbl_fehler
+if ($result = @$db->db_query("SELECT conname FROM pg_constraint WHERE conname = 'uk_tbl_fehler_fehlercode_fehler_kurzbz'"))
+{
+	if ($db->db_num_rows($result) > 0)
+	{
+		$qry = "ALTER TABLE system.tbl_fehler DROP CONSTRAINT uk_tbl_fehler_fehlercode_fehler_kurzbz;";
+
+		if (!$db->db_query($qry))
+			echo '<strong>system.tbl_fehler '.$db->db_last_error().'</strong><br>';
+		else
+			echo '<br>Removed UNIQUE constraint on "fehlercode" and "fehler_kurzbz" from system.tbl_fehler<br>';
+	}
+}
+
+// Add NOT NULL constraint on fehler_kurzbz and fehlercode_extern on system.tbl_fehler
+if ($result = @$db->db_query("SELECT conname FROM pg_constraint WHERE conname = 'chk_tbl_fehler_fehler_kurzbz_fehlercode_extern'"))
+{
+	if ($db->db_num_rows($result) == 0)
+	{
+		$hasError = false;
+		$qry = "SELECT 1 FROM system.tbl_fehler WHERE fehler_kurzbz IS NULL AND fehlercode_extern IS NULL AND fehlercode = 'UNKNOWN_ERROR'";
+
+		$result = $db->db_query($qry);
+		if ($db->db_num_rows($result)>0)
+		{
+			// Add fehler_kurzbz TO UNKNOWN_ERROR to satisfy constraint
+			$qry = "UPDATE system.tbl_fehler SET fehler_kurzbz='unbekannterCoreFehler' WHERE fehlercode = 'UNKNOWN_ERROR';";
+
+			if(!$db->db_query($qry))
+			{
+				echo '<strong>system.tbl_fehler '.$db->db_last_error().'</strong><br>';
+				$hasError = true;
+			}
+			else
+			{
+				echo '<br>Add fehler_kurzbz to UNKNOWN_ERROR in system.tbl_fehler';
+			}
+		}
+
+		if (!$hasError)
+		{
+			$qry = "ALTER TABLE system.tbl_fehler ADD CONSTRAINT chk_tbl_fehler_fehler_kurzbz_fehlercode_extern CHECK (fehler_kurzbz IS NOT NULL OR fehlercode_extern IS NOT NULL);";
+
+			if (!$db->db_query($qry))
+				echo '<strong>system.tbl_fehler '.$db->db_last_error().'</strong><br>';
+			else
+				echo '<br>Added NOT NULL constraint on "fehlercode" and "fehler_kurzbz" from system.tbl_fehler<br>';
+		}
+	}
+}
diff --git a/system/fehlerupdate.php b/system/fehlerupdate.php
index 1a8b705e6..98204315a 100644
--- a/system/fehlerupdate.php
+++ b/system/fehlerupdate.php
@@ -106,7 +106,210 @@ $fehlerArr = array(
 		'fehlertext' => 'Erworbene ECTS fehlen (Meldepflicht bei Outgoings >= 29 Tage Monat im Ausland)',
 		'fehlertyp_kurzbz' => 'error',
 		'app' => 'core'
+	),
+
+	/** Plausichecks **/
+	array(
+		'fehlercode' => 'CORE_INOUT_0007',
+		'fehler_kurzbz' => 'IncomingHeimatNationOesterreich',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Heimatnation bei Incoming Österreich',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_INOUT_0008',
+		'fehler_kurzbz' => 'IncomingOhneIoDatensatz',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Incoming hat keinen IO Datensatz (prestudent_id %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_INOUT_0009',
+		'fehler_kurzbz' => 'IncomingOrGsFoerderrelevant',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Incoming oder gemeinsames Studium ist nicht als nicht förderrelevant markiert. (prestudent_id %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_STG_0001',
+		'fehler_kurzbz' => 'StgPrestudentUngleichStgStudent',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Studiengang des Prestudenten ist ungleich dem Studiengang des Studenten. (prestudent_id %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_STG_0002',
+		'fehler_kurzbz' => 'OrgformStgUngleichOrgformPrestudent',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Es ist kein Studienplan mit Studiengang (%s) und Organisationsform (%s) des Studenten zugewiesen. (prestudent_id %s, Studiensemester %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_STG_0003',
+		'fehler_kurzbz' => 'PrestudentMischformOhneOrgform',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Organisationsform ist für Studierenden/BewerberIn in Mischformstudiengang nicht eingetragen. (prestudent_id %s, Studiensemester %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_STG_0004',
+		'fehler_kurzbz' => 'StgPrestudentUngleichStgStudienplan',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Studiengang des Prestudenten passt nicht zu Studiengang des Studienplans. (prestudent_id %s, Studienplan %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_STUDENTSTATUS_0001',
+		'fehler_kurzbz' => 'AbbrecherAktiv',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'AbbrecherIn hat aktiven Benutzer. (prestudent_id %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_STUDENTSTATUS_0002',
+		'fehler_kurzbz' => 'StudentstatusNachAbbrecher',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Aktiver Status nach Abbrecher Status. (prestudent_id %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_STUDENTSTATUS_0003',
+		'fehler_kurzbz' => 'AusbildungssemPrestudentUngleichAusbildungssemStatus',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Ausbildungssemester %s des aktuellen Status stimmt nicht mit Ausbildungssemester %s bei StudentIn (Lehrverband) überein. (student_uid %s, prestudent_id %s, Studiensemester %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_STUDENTSTATUS_0004',
+		'fehler_kurzbz' => 'InaktiverStudentAktiverStatus',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Inaktiver Benutzer hat aktiven Status. (prestudent_id %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_STUDENTSTATUS_0005',
+		'fehler_kurzbz' => 'InskriptionVorLetzerBismeldung',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Datum der Inskription liegt vor dem Datum der letzten BIS-Meldung %s. (prestudent_id %s, Studiensemester %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_STUDENTSTATUS_0006',
+		'fehler_kurzbz' => 'DatumStudiensemesterFalscheReihenfolge',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Datum und Studiensemester sind bei den Status in falscher Reihenfolge. (prestudent_id %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_STUDENTSTATUS_0007',
+		'fehler_kurzbz' => 'AktiverStudentOhneStatus',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Aktive/r StudentIn ohne aktuellen Status (prestudent_id %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_STUDENTSTATUS_0008',
+		'fehler_kurzbz' => 'StudienplanUngueltig',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Studienplan %s ist im Ausbildungssemester %s nicht gültig (prestudent_id %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_STUDENTSTATUS_0009',
+		'fehler_kurzbz' => 'FalscheAnzahlAbschlusspruefungen',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Mehrere oder keine bestandenen Abschlussprüfungen (prestudent_id %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_STUDENTSTATUS_0010',
+		'fehler_kurzbz' => 'DatumAbschlusspruefungFehlt',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Kein Abschlussprüfung Datum (prestudent_id %s, abschlusspruefung_id %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_STUDENTSTATUS_0011',
+		'fehler_kurzbz' => 'DatumSponsionFehlt',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Kein Sponsionsdatum (prestudent_id %s, abschlusspruefung_id %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_STUDENTSTATUS_0012',
+		'fehler_kurzbz' => 'BewerberNichtZumRtAngetreten',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Bewerber nicht zum Reihungstest angetreten (prestudent_id %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_STUDENTSTATUS_0013',
+		'fehler_kurzbz' => 'AktSemesterNull',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Aktuelles Ausbildungssemester ist 0 (prestudent_id %s, Studiensemester %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_STUDENTSTATUS_0014',
+		'fehler_kurzbz' => 'AbschlussstatusFehlt',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Kein Abschlussstatus (prestudent_id %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_PERSON_0001',
+		'fehler_kurzbz' => 'GbDatumWeitZurueck',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Geburtsdatum vor dem 01.01.1920',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_PERSON_0002',
+		'fehler_kurzbz' => 'NationNichtOesterreichAberGemeinde',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Nation der Adresse ist ungleich Österreich, es ist aber eine österreichische Gemeinde (%s) angegeben (adresse_id %s)',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_PERSON_0003',
+		'fehler_kurzbz' => 'FalscheAnzahlHeimatadressen',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Es sind mehrere oder keine Heimatadressen eingetragen',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
+	),
+	array(
+		'fehlercode' => 'CORE_PERSON_0004',
+		'fehler_kurzbz' => 'FalscheAnzahlZustelladressen',
+		'fehlercode_extern' => null,
+		'fehlertext' => 'Es sind mehrere oder keine Zustelladressen eingetragen',
+		'fehlertyp_kurzbz' => 'error',
+		'app' => 'core'
 	)
+	/** Plausichecks end **/
 );
 
 // Loop through the filters array
@@ -131,11 +334,11 @@ for ($fehlerCounter = 0; $fehlerCounter < count($fehlerArr); $fehlerCounter++)
 	{
 		$selectFehlerQuery = 'SELECT 1
 								FROM system.tbl_fehler
-							   WHERE fehlercode = '.$db->db_add_param($fehler['fehlercode']);
+								WHERE fehlercode = '.$db->db_add_param($fehler['fehlercode']);
 
 		// If no error occurred while loading a fehler from the DB
-	   	if ($dbFehlerDefinition = @$db->db_query($selectFehlerQuery))
-	   	{
+		if ($dbFehlerDefinition = @$db->db_query($selectFehlerQuery))
+		{
 			// If NO filters were loaded: insert
 			if ($db->db_num_rows($dbFehlerDefinition) == 0)
 			{