Some users reporting strange issues

A very odd problem has started happening with my Joomdle system.

We set it up earlier this year, and it has been working well for months. But now suddenly we've started getting users reporting issues.

Firstly, users are reporting that they can't get to the Moodle course content. They have logged in to Joomla, and their accounts have all the necessary permissions, but when they try to access anything on Moodle, they are given the site homepage (on Joomla) with "You are not authorised to view this resource".

My analysis is that the 'not authorised' message is a red herring. This is coming up because Moodle thinks the user isn't logged in, and is redirecting them to the Joomla login page. But Joomla is logged in and the Joomla login page has 'Guest-only' access, thus you get the 'not authorised' message.

Other users are reporting a similar problem when they try to log out. Joomla is failing to log them out, and is instead giving them the same 'not authorised' message when it tries to show them the login screen.

Note that this only applies to some users, and is not related to their account -- we are able to log in using the same credentials, and we do not see the problem. Likewise, one of the users with the issue was able to test it using a different machine, and it worked fine. Many other users are continuing to access the site unaffected.

I haven't been able to work out any pattern to the errors -- I can't see any reason why one user would get these issues while another doesn't. I'm also at a loss to explain why it suddenly started happening to multiple users, because as far as I can tell, nothing changed in the system.

It seems to be linked to Joomdle, but as I'm unable to reproduce it for myself, it's really hard to diagnose it.

Does anyone here any any ideas what it might be, or what I could do to work it out?

Thanks for any help.


Simon C.

Hi Simon.

As you say, when you can't replicate a problem it's much more difficult to investigate
First thing is to make sure system check keeps being all green.
Then, you would need to somehow try to replicate the problem, so we can try to debug. Otherwise, there's not much I can tell you.

I have never heard of a similar behaviour: when a user/site has SSO problems, problem happened always for that user/site.