(UPDATED) After we installed the Latest Lync server 2013 security fix (Security Update for Lync Server 2013 Web Components Server KB3080353) we have had severeal issues where users where unable to sign in to Lync. This was the server complaining about the client certificate , normally it is the client complaining about the server certificate.
Particulary users homed on VDI or Citrix /RDS and also some CommonareaPhones where affected. Inspecting the client log from a user login revealed :
There was an error communicating with the endpoint at ‘https://lyncserver.domain.local/WebTicket/WebTicketService.svc/mex’.
The server returned HTTP status code ‘500 (0x1F
09/18/2015|11:34:46.551 46A8:461C INFO :: CUccPlatform::WriteStreamToLog:
09/18/2015|11:34:46.551 46A8:461C INFO :: 4)’ with text ‘Internal Server Error’.
The server was unable to process the request.
This looked likt it had something to do with the webserver part of lync. This is why we consentrated on the KB3080353 update.
Or delete the file containing the client cert from:
For a global fix we had to uninstall this update and reboot the server. All of the affected server was Lync server standard edition.
Had one server where a uninstall failed. Solution for this was to download latest Lync server 2013 CU and apply that. Once that was done all seems fine , except we now had on issue where IOS products would fail to connect. Error message was the they had to get the newest Lync 2013 client even if they was running latest. Turned out this was a bug :
“You can’t sign in with this version of Lync. Please install a newer version. If that doesn’t work, contact your support team.”
“You can’t sign in with this version of Lync” error in Lync for iPad or Lync for iPhone on iOS 9. When I testet this bug was affecting more than IOS9, even older versions failed.