Outgoing calls from teams dropped

Occasional Contributor

All outgoing calls are being dropped after about 10 seconds of silence with Q.850 ;cause=22 being returned to the SBC and the following error displayed to the user:

MicrosoftTeams-image (19).png

It only happens in one of our offices if the same account logs into a machine in a different office it's fine and it never occurs on the WebClient only the desktop client.


Anyone seen this before?  

3 Replies
best response confirmed by Dan____ (Occasional Contributor)

In case anyone comes across this post in future, it turned out to be a firewall issue whereby one of the MSFT servers was blocked, but this did not affect the regular Teams usage at all only PSTN it also didn't effect the Teams web client

Hey @Dan____ having the same issue on our side but on handsets. What were the MSFT servers that were blocked?


@Henry MoralesUnfortunately I don't remember our exact case but I think it was to do with there is a docs page on the SIP signaling fqdns that can be found here that might help.


Hope that is able to point you in the right direction.