Cisco Jabber version 11.8.3
ENS Firewall 10.5.0.331
Internet Explorer, Firefox, Chrome
"ciscojabber.exe" is a trusted executable in the firewall 'common' policy
policy enforcement is set to 5 minutes
we regulate application access to our internet proxy server. all three browsers mentioned above are allowed access to the proxy server. we have a named rule to block application access as well as a named block all.
Recently, we upgraded to the above version of jabber. I have made no changes to the firewall. We now have a small subset of users that are having issues. Specifically, jabber will go in 'offline' mode and, when that happens, internet access is blocked. This happens about every five minutes and lasts a couple of minutes. It is quite irritating to those users who have the problem. The odd thing is that local network access remains working. The browsers, however, show blocks not by any of our named blocks but by the default "Block All".
If I disable the firewall, however, jabber never goes offline and browser access to the server remains.
To make it even stranger, it does not seem to be affecting any Windows 10 systems, only Windows 7.
I'm not inclined to believe it is McAfee because it isn't affecting *everyone* but I have a user base that is hell bent on blaming the security product. Any information that can be provided would be greatly appreciated and welcomed!