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Dan____'s avatar
Dan____
Brass Contributor
May 29, 2020
Solved

Outgoing calls from teams dropped

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: It only happens in one of o...
Calling
Direct Routing
  • Dan____'s avatar
    Dan____
    Jun 12, 2020

    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

Henry Morales's avatar
Henry Morales
Brass Contributor
Feb 15, 2021
Hey Dan____ having the same issue on our side but on handsets. What were the MSFT servers that were blocked?

Thanks
Dan____'s avatar
Dan____
Brass Contributor
Feb 19, 2021

Henry MoralesUnfortunately I don't remember our exact case but I think it was to do with sip.pstnhub.microsoft.com there is a docs page on the SIP signaling fqdns that canhttps://docs.microsoft.com/en-us/microsoftteams/direct-routing-plan#sip-signaling-fqdns that might help.

 

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

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