diff --git a/system/dbupdate_3.4.php b/system/dbupdate_3.4.php
index bc8152a90..2631b64c8 100644
--- a/system/dbupdate_3.4.php
+++ b/system/dbupdate_3.4.php
@@ -32,6 +32,7 @@ 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');
 require_once('dbupdate_3.4/19154_beurteilungsformulare_pruefungssenat.php');
+require_once('dbupdate_3.4/13011_installation_on_multiple_servers.php');
 
 // *** Pruefung und hinzufuegen der neuen Attribute und Tabellen
 echo '<H2>Pruefe Tabellen und Attribute!</H2>';
diff --git a/system/dbupdate_3.4/13011_installation_on_multiple_servers.php b/system/dbupdate_3.4/13011_installation_on_multiple_servers.php
index 24c496457..22f8b20f9 100644
--- a/system/dbupdate_3.4/13011_installation_on_multiple_servers.php
+++ b/system/dbupdate_3.4/13011_installation_on_multiple_servers.php
@@ -3,34 +3,47 @@
 if (! defined('DB_NAME')) exit('No direct script access allowed');
 
 // stud_selfservice boolean fuer public.tbl_vorlage
-if(!@$db->db_query("SELECT server_kurzbz FROM system.tbl_extensions LIMIT 1"))
+if (!@$db->db_query("SELECT server_kurzbz FROM system.tbl_extensions LIMIT 1"))
 {
 	$qry = "ALTER TABLE system.tbl_extensions ADD COLUMN server_kurzbz varchar(64);
 			ALTER TABLE system.tbl_extensions ADD CONSTRAINT fk_extensios_server_kurzbz FOREIGN KEY (server_kurzbz) REFERENCES system.tbl_server(server_kurzbz) ON UPDATE CASCADE ON DELETE RESTRICT;";
 
-	if(!$db->db_query($qry))
+	if (!$db->db_query($qry))
 		echo '<strong>App: '.$db->db_last_error().'</strong><br>';
 	else
 		echo '<br>Neue Spalte server_kurzbz in system.tbl_extensions hinzugefügt';
 }
 
 
-// UNIQUE INDEX uidx_extensions_name_version_server
-if ($result = $db->db_query("SELECT 0 FROM pg_class WHERE relname = 'uidx_extensions_name_version_server'"))
+// UNIQUE INDEX uidx_extensions_name_version
+if ($result = $db->db_query("SELECT COUNT(*) FROM pg_class WHERE relname = 'uidx_extensions_name_version'"))
 {
-	if ($db->db_num_rows($result) == 1)
+	$countObj = $db->db_fetch_object($result);
+
+	// If exists then drop it
+	if ($countObj->count == '1')
 	{
 		$qry = 'DROP INDEX system.uidx_extensions_name_version';
 		if (!$db->db_query($qry))
-			echo '<strong>uidx_extensions_name_version_server '.$db->db_last_error().'</strong><br>';
+			echo '<strong>uidx_extensions_name_version '.$db->db_last_error().'</strong><br>';
 		else
-			echo '<br>Dropped unique uidx_extensions_name_version_server';
+			echo '<br>Dropped unique uidx_extensions_name_version';
 	}
 
-	$qry = 'CREATE UNIQUE INDEX uidx_extensions_name_version_server ON system.tbl_extensions USING btree (name, version, server_kurzbz);';
-	if (!$db->db_query($qry))
-		echo '<strong>uidx_extensions_name_version_server '.$db->db_last_error().'</strong><br>';
-	else
-		echo '<br>Created unique uidx_extensions_name_version_server';
+	// UNIQUE INDEX uidx_extensions_name_version_server
+	if ($result = $db->db_query("SELECT COUNT(*) FROM pg_class WHERE relname = 'uidx_extensions_name_version_server'"))
+	{
+		$countObj = $db->db_fetch_object($result);
+
+		// If does not exist then create it
+		if ($countObj->count == '0')
+		{
+			$qry = 'CREATE UNIQUE INDEX uidx_extensions_name_version_server ON system.tbl_extensions USING btree (name, version, server_kurzbz);';
+			if (!$db->db_query($qry))
+				echo '<strong>uidx_extensions_name_version_server '.$db->db_last_error().'</strong><br>';
+			else
+				echo '<br>Created unique uidx_extensions_name_version_server';
+		}
+	}
 }