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Hello, 
I am trying to get deeper into ExpressionScript und for this reason I loaded the sample survey LS3_Validation_tests.zip from this  page . I can open everything and see the survey - but I guess that all the settings are in Survey logic file, right? At least I cannot see any expressions in the questions. 
But when I try to open the Survey logic file, I get an error (see attachment). 

My questions:
Are all the expressions really in Survey logic file?
Are there any other ways to open it? (I am trying to open it via Survey - Tools - Survey logic file)
Thanks 
Ralf
 

Expressions are NOT in the survey logic file. They are usually in the question text or in the relevance equations, etc of each question or question group.

Nevertheless, the survey logic file should appear (and you can usually also see the equations in the survey logic file, but you can't edit them).

This sample survey does not use any "question validation equation"

It shows validation by attributes
 
and regular expression
 
entered in "Eingabevalidierung"
 

And you see, I do not see any issue opening the logic file (version 5.6.40)

Joffm

Surely PHP version issue related.

No issue on 6.3.7 /PHP8.1
No issue on 5.6.48 / PHP7.4

Thanks for the answers so far and I found out in the meanwhile that I can access (parts of) the survey logic file in the question groups and the questions itself.
But if I cannot change the conditions in the survey logic file - where do I find them?
Let's use the example from Joffm, question num. It has a validation by attributes and a regex validation.
I found the validation by attributes after a long search finally in the question - Condition designer.
But where do I find the regex validation? In question - Condition designer the option RegEx is greyed out, the input validation field inside the question it is empty (Joffm: Eingabevalidierung is empty). The question group has no condition designer... I just cannot find it! Can you guys point me in the right direction?
Ralf

What is your PHP version ?

Els e: why you don't update your LimeSurvey version ? Maybe it's fixed in last version.

I test with php8.1 , no debug and LimeSurvey 5.6.48 : it's OK.

LimeSurvey 5 (last version) are not compatible officially with PHP8.1 because we can not activate debug mode. But it work without debug mode.

Using PHP 8.1...

I am continuously running surveys... there is no time "in between" to update. But maybe, when problems are occuring, I just have to do it at night, when nobody's answering anyway.

If you update via SSH/CLI directly less than 2 minutes to update.

I update via GIT : the most quick because it update only needed file.
I think CompfortUpdate do the same : only needed files updated : more quick.

If you update continuously : it the most quick and can be transparent for user in most case.

There is never a perfect time for updates. At one point you just have to do it. With comfort update it takes you a couple of minutes and Denis has also mentioned a couple of other quick methods to update.

There are certainly times when there are usually a lot less or no responses coming in. And if really someone starts a survey in the exact 5 minutes while you run the update, so be it. These things happen.

Thanks again for the push... I updated now and you were right: now I can see the survey logic file.
Also a great suggestion to set up GIT - I really gonna do it!

Furthermore I am a little confused: I received an Email from the forum which says, that Joffm posted a message but I cannot find that message in the thread:

A new reply has been posted on the LimeSurvey Forums
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Message Subject : Survey logic file at sample survey LS3 shows error

Category : Can I do this with LimeSurvey?

Posted by : Joffm

URL : forums.limesurvey.org/forum/can-i-do-thi...rvey-ls3-shows-error

Message:
Hi,

But if I cannot change the conditions in the survey logic file - where do I find them?

and 
I found the validation by attributes after a long search finally in the question - Condition designer.


Don't you see it here?
Let's take question "afAMF"
In the overview you see this
 
The min and max  number of answers is tay<ken from question "minselect" and "maxselect"
and the range from questions "num" and "num2"

This you see here
 
and here
 

Now the Regular expression
In question "vS" you see in the overview
 
and the RegEx is entered here
 


Niw "Condition Designer"???:
In this sample survey there are no conditions on questions at all.
All questions are shown. So no conditions referring to resilts of previous questions.

If you see something different, you should show ar least a screenshot.


But as I understood your main problem is the not showing "survey logic file".
That's unpleasant, but as it is only an overview of what you see (better) in the questions themselves.


Joffm

How can this happen? 
And unfortunately I cannot follow the suggestions because the mail does not show the inserted screenshots. 
Or let's try it like this: Joffm, could you please post your last message again? 
Thanks, Ralf