Quiz and question banks

There could be various causes, and to investigate futher, the advice I just gave in https://moodle.org/mod/forum/discuss.php?d=436765#p1757889 applies.

One thing that can cause this problem is to do with which sign-in system you are using. So, which authentication plugin are you using?

I'll certainly be watching to see where this one goes and anyone else that's battled this error. We battle this one multiple times almost every week and have been for years through several versions of moodle, and I'm not exaggerating one bit. First things first, to keep the student moving with the quiz when it locks out with this error we have them do "Ctrl + Alt + Delete" and then a menu pops up and we have them to choose the "sign out" option. This takes them back to their Desktop where they can login again and go to that same quiz and finish it, but they lose the time it takes from the time they get bumped out till they get back in. We tell the students about this error ahead of time so they know what to do.

As for why this happens, I can't tell you for sure but I believe it's due at least in part to a poor / choppy internet signal and here's why I say this. We are probably unique in our use of moodle because our training is short term and corporate sponsored. We own and provide the computer/devices used during their training and many of the students are attending from out of town so they stay in a nice hotel that we arrange for them. So it's our devices running on hotel internet. I give out my cell phone number in case anyone has trouble during the quizzes and it's rare that I get just one call when it happens. Over the years we've had several brands of devices and some are more prone than others to have this error so I suspect these devices do not have as strong of WiFi cards. For instance, at 9:17 pm on Monday night I can get several calls at once with this error and then the system works perfectly the rest of the week. I do recognize that multiple errors coming from the same IP address can look like an attack on the server so our web guy has those IP's white listed to ease the pain.

We teach diagnostics (not on computer stuff) and I fully understand that "correlation" does not necessarily mean "causation", so just because these items are related doesn't mean one caused the other. However, in our case I do believe the cause and effect are related. Another thing is many times after this error occurs we find that the device(s) gets hit with an update of some kind (usually Windows) so a lot of internet and processor resources are being consumed. I get the idea that if moodle doesn't send/receive in a certain time frame that it hangs up but that's just a hunch. At one time our web guy followed the pathway to and from the server and made some changes for more direct routing that seemed to help. Like I mentioned, I've been fighting this one for years and I can say for sure that better equipment and better internet helps greatly and If Windows would still allow you to do manual updates that would help also.

I hope this helps,
Mark