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Your LimeSurvey version: 3.25.17+210309
Own server or LimeSurvey hosting: Own Servers on AWS Linux EC2 instances w/NGINX and MySQL RDS

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We have been getting intermittent "Could not open temporary upload directory errors" but it happens randomly.  Sometimes we get the error while working within the Limesurvey admin console, but we have also heard of end users taking surveys getting these errors intermittently when answering or submitting the surveys.  Because its intermittent we are not able to reproduce it consistently.

From searching, I found this thread from almost 9 year ago  forums.limesurvey.org/forum/installation...-temporary-directory
And I have confirmed that the suggested fix of the PCLZIP library is currently up to date.  And I also checked that the nginx user has read/write permissions and ownership of the /limesurvey/tmp directory like the Limesurvey CE installation manual has listed.  Has anyone else encountered this issue?

3.25.17+210309

Can't say anything about the issue itself, but you might want to start with updating to the most recent version of the software.

Your version is almost 2 years old and hasn't received any updates, bug or security fixes since 09/03/2021.

In my opinion, it doesn't make sense trying to find bugs or reproduce errors with a software that is completely outdated.

The most current version of the LS branch that you are using (LS3) is 3.28.45+230117 so it seems like there have been a lot of updates since.

This doesn't mean your problem will be fixed with an update, but at least you can make sure that it wasn't something in your specific version and has long been updated since.

So before doing anything else, I would highly recommend to update to the latest version and see if the errors continue. Then you can start bug hunting.

awdlgt wrote:

Because its intermittent we are not able to reproduce it consistently.
 

Couldn't it be something specific to the AWS environment?
If you use this LimeSurvey version for a long time on that setup I don't think it's an issue inside LimeSurvey.
I haven't seen that error message in posts or bug reports very often. Perhaps I overlooked a few, but I would check if the AWS environment changed.