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LimeSurvey version: LimeSurvey version 6.13.2, LimeSurvey build 250506, PHP v8.2.28

Own server or LimeSurvey Cloud: Own installation with an ISP
Survey theme/template: modified/inherited from fruity_twentythree
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Fresh install, only some change to a default theme, handful of questions. No issues during test running the survey. NOw, for the first run the survey activated with email invites and after first iteration of going through the entire survey and submitting this error pops up under URL www.*.com/index.php/724896:500: Internal Server Error - Call to a member function decryptBeforeOutput() on nullAn internal error occurred while the Web server was processing your request. Please contact SBI Survey Admin to report this problem.

 

LimeSurvey version 6.13.2, LimeSurvey build 250506, PHP v8.2.28

You did a fresh install with a version that is 2 months old? We are currently at 6.15.2 ( community.limesurvey.org/downloads/ ).

Is any part of your survey encrypted?
Do you use admin notifications to send emails at the end of the survey?

Thanks.

1. A minor version increase from 6.13 to 6.15 is surely not an explanation of a 500 server error when LS is at major version 6 after more than a decade.
2. no encryption, unless I overlooked an encrypted default somewhere...?
3. If I understand correctly: yes, the admin sent an email to the respondent. Does that reliably imply the answer was recorded?

 
A minor version increase from 6.13 to 6.15 is surely not an explanation of a 500 server error when LS is at major version 6 after more than a decade.
 

Limesurvey 6 was released about 2 years ago, not quite a decade ( www.limesurvey.org/blog/product-news/limesurvey-6 )

But what makes you think that bugs can't sneak in after a while? Things happen. Just last week there was a bug that caused some trouble for some users (If I recall right it cause an 500 error, don't remember what happened exactl).

This doesn't need to be something huge. I personally would update to the latest version just to make sure that it isn't something with my version, before I continue bug hunting. Sometimes it can be a small typo that is introduced, that can have a huge impact. Not saying this is the case here, but I would recommend to exclude the version as a source of the problem.

no encryption, unless I overlooked an encrypted default somewhere...?

OK, usually no default. Sometimes you could set a question as encrypted in the data base. I am shooting in the dark here based on the error message you are providing that mentions encryption.

If I understand correctly: yes, the admin sent an email to the respondent.

No, I am talking about the option for sending an admin notification to a specific email when a questionnaire is submitted. If there are isses with sending the email, Limesurvey sometimes behaves strange.

Does that reliably imply the answer was recorded?

Only you can check if an answer was recorded. You can access all recorded answers in the backend.

However, as Limesurvey saves collected data always when a respondent clicks the "next" button, the answers should be recorded at least until the last "page" of your questionnaire, even if the final sending was not successful. Have a look at the response table and see if this has been registered as a complete or if it only registered data up to the last page. Now, if you have all questions on one page Limesurvey obviously only saves data if the final button was clicked and it was sucessful.

Here you can see what has changed since LS 6.13.2:

github.com/LimeSurvey/LimeSurvey/commit/...70415a0b7d7a51763da4

Thank you, @holch.

Okay, will do the update and then check settings for admin emails. Will report back but may take until next weeks due to other stuff...

Thanks again.

Here you find the information about the admin notifications:
www.limesurvey.org/manual/manual/Notifications_&_data/en

If you don't use them in this case, we can exclude them as an issue for the error at the end of the survey already.

holch wrote:

I am shooting in the dark here based on the error message you are providing that mentions encryption.

If I understand correctly: yes, the admin sent an email to the respondent.

The encryption functions of PHP are used when mail account credentials are saved. I recommend to invest a few minutes checking the php version and extensions used. Depending on the webhosting used it helps switching the php version and preselected extensions to see if the issues vanishes.

This issue has been reported before. But wasn't investigated or solved.
bugs.limesurvey.org/view.php?id=19695