This called for some freestyle troubleshooting. It wasn’t long before I realized that while there’s plenty of references similar to “No connection could be made because the target machine actively refused it,” very few of them were directly related to Skype for Business and of the ones that were, they weren’t related to the Call Park service. I hit the interwebs to see what other people found. The root cause was a bit deeper than that, it seemed. A quick check confirmed that IPv6 was enabled on the server’s NIC, so I disabled it, restarted the services, and hey! RTCCPS is started. It’s trying to open a port on the server’s IPv6 interface and this client doesn’t use IPv6. Looking at this log, it’s pretty obvious what the problem is. I must say, I was actually a bit happy to see that an error had been logged:

Now I’ve got a timeframe for when it stopped, so it’s time to look at the event logs. Looking back at the services, it stopped again. I refreshed a couple times, it stayed running, so I contacted the client and asked them to test. I manually started the service, ran Get-CsWindowsService, and there it was, running. In checking the services, sure enough, I saw that RTCCPS was in a stopped state. After installing the November 2016 Cumulative Update, everything appeared to be working, but a couple of days after the install, I got a report that Call Park wasn’t working. One of the items that we were working on was to get their Skype for Business infrastructure up to date with the latest updates and Cumulative Updates.

Another consulting company had set up their Skype for Business environment and while it’d been chugging along for almost a half a year, the client had been seeing some strange activity and brought us in to review and remediate as needed.

I’ve been working on a remediation project for a client. Have you ever run into an issue with Skype for Business that no matter how hard you look for an answer, you just can’t seem to find one? I found myself in that position recently and while it’s a bit embarrassing at how obviously simple the answer turned out to be, I think it’s worth sharing in case someone else finds themselves in this same predicament.

Skype won39t start