sporadically ICAP error when using Endian Proxy

[Guest]

[St3pp0]

Dear Endian-Users and Experts,

I am facing the following issue:

In of our schools we manage, we have a physical appliance running Endian(currently 3.3.0 - I updated yesterday, but that didn't do the trick). Endian is used here for proxy, firewall and routing and was working fine during the last years.

Now however the IT-teacher reports that on multiple times per day students have issues accessing web pages and are getting presented with an "ICAP error". Students use Mozilla Firefox in latest ESR version

This is an example from 16th of September with times when the issue occurred:

0800-0824
0830-0850
1030-1039
1047-1052
1112-1122

We have a MS Server hosting the AD and GPO policy where Endian proxy is set at the Firefox GPO settings, so that each student has it enabled when logging in.

I have checked the log files already, but nothing is related to the mentioned ICAP error there. I have attached the system logfiles from 16.9.2020

Let me know if further information is needed.

Your help on this is much appreciated, as I have already googled my a** off ;-)

Kind Regards
Sebastian