SfB: An exception has been thrown in processing BeginApplyMediaLines

Just a small one I was fighting for a solid half hour, wasn’t popping up a lot in Bing and I let my mind get overwhelmed for a moment. Thought I’d toss it here in case anyone ended up fighting the same issue.

This was a Skype for Business Server (mixed 2015 and 2019) environment where the virtual infrastructure took a complete loss and everything had to be restored overnight. Everything came back online and seemed to be working well, but calling was failing. All services were running, the event log was nearly free of errors. Rebooted everything for good measure, still no calling. The debug logger was throwing the following error:

ms-diagnostics: 10014;source=”mediation.ad.domain.com”;reason=”An internal exception received while processing the incoming request”;component=”MediationServer”;Exception=”An exception has been thrown in processing BeginApplyMediaLines”
ms-diagnostics-public: 10014;reason=”An internal exception received while processing the incoming request”;component=”MediationServer”;Exception=”An exception has been thrown in processing BeginApplyMediaLines”

I stared at that for a moment and my brain started to overthink the issue and my itchy fingers went right to an Internet search which was revealing little. I’m thinking corrupted or mismatched DLL, reinstall patches, and on and on… the AudioCodes syslogger however revealed a much more clear error. “Classification Failed”. That error basically means the session border controller can’t validate that the call is coming from an approved source. We checked the IP addresses and there it was. The restore had created a new virtual NIC which was stuck on DHCP. Putting the static IP back on, and rebooting everything to get back online quickly (probably didn’t need to, but just in case anything is hard cached) put it all back to normal.

They were lucky… I’ve seen so much worse after complete restores.