20355: Not able to upgrade from Limesurvey community version 6.15.1 to newer version when running on MSSQL DBMS

This issue affects 1 person(s).

ID	Project	Category	View Status	Date Submitted	Last Update

20355	Bug reports	ComfortUpdate	public	2025-11-18 10:49	2025-11-21 23:24

Reporter	msvojsik	Assigned To	p_teichmann
Priority	none	Severity	crash
Status	assigned	Resolution	open
Product Version	6.6.x

Summary	20355: Not able to upgrade from Limesurvey community version 6.15.1 to newer version when running on MSSQL DBMS
Description	While trying update to newer version, the update fails because of T-SQL syntax error with the following details: Syntax error in upgrade script for MSSQL DBMS. Upgrade fails when trying to upgrade from DB version 633 (Limesurvey 6.15.0) or 634 (Limesurvey 6.15.1) to 636 (Limesurvey 6.15.4 or newer) with the following error: CDbCommand failed to execute the SQL statement: SQLSTATE[42000]: [Microsoft][ODBC Driver 18 for SQL Server][SQL Server]Incorrect syntax near the keyword 'backup'. \application\helpers\update\updates\Update_636.php, line 20
Steps To Reproduce	Steps to reproduce Upgrade fails when trying to upgrade from DB version 633 (Limesurvey 6.15.0) or 634 (Limesurvey 6.15.1) to 636 (Limesurvey 6.15.4 or newer) Expected result successfull upgrade Actual result upgrade fails
Tags	No tags attached.

Bug heat	2
Complete LimeSurvey version number (& build)	6.15.0 (build 250623)
I will donate to the project if issue is resolved	Yes
Browser
Database type & version	MSSQL Server 2022
Server OS (if known)	Windows server 2022
Webserver software & version (if known)	IIS 10
PHP Version	8.3.27

User List	There are no users monitoring this issue.

Date Modified	Username	Field	Change
2025-11-18 10:49	msvojsik	New Issue
2025-11-21 23:23	c_schmitz	Note Added: 83911
2025-11-21 23:23	c_schmitz	Bug heat	0 => 2
2025-11-21 23:24	c_schmitz	Assigned To	=> p_teichmann
2025-11-21 23:24	c_schmitz	Status	new => assigned

c_schmitz 2025-11-21 23:23 administrator ~83911	@msvojsik I think somewhere you have a table in your database which you created/rename manually containing the word 'token' and 'backup' or similar. like 'token_backup_12345' If you remove that table the update should work.