Error message when students are testing

Error message when students are testing

by Edward Delaney -
Number of replies: 2

I am new to Moodle and am using it on an intranet in a class today on a Windows 2012 server (Moodle 3.3).

I have 28 students. All logged in, updated user profiles, and enrolled in the course with no issues. We administered a pre-test and that is when we ran into our issue. 25 users had no issue in the test. 3 were presented with the following error:

Coding error detected, it must be fixed by a programmer: Failed to unserialise data from file. Either failed to read, or failed to write.

They could not refresh to get passed it. We closed the browser and tried to have the students log back in. Once they signed in they received the same issue.

I downloaded the three profiles, deleted their user accounts, and then uploaded the information again and now they can login.

My reading tells me this is a cache issue. I read the following today:

1.Execute script purgecaches to reset the cache system. (php /moodle/admin/cli/purge_caches.php)

Does this sound like it may be the problem? How can I run this in a Windows environment?

I will be trying to recreate the issue after class today with the students. Is there something I should specifically test? Is there a way for me to resolve this issue without a PHP background?


Average of ratings: -
In reply to Edward Delaney

Re: Error message when students are testing

by Rex Lorenzo -

We go the same error message when our web server rebooted because of a kernel panic. So was the Windows server unexpectedly shutdown? That might cause a corruption in the cache. Else, it should be a rare occurrence if the computer is shut down properly.

Average of ratings: Useful (2)
In reply to Rex Lorenzo

Re: Error message when students are testing

by Edward Delaney -

Thanks for the response. We have to bring some Moodle expertise into the organization. Right now I am not sure how to check for the corrupted file but since we did not have issues in our initial testing, we are going to reinstall, start from scratch and see if that fixes the issue. If it does, I think that will point to the corrupted file issue.

I believe we did have an unexpected shutdown at one point last week. I will let you know if this fixed the issue.