Q.850, cause=79 Transport profile not recognized

Ramesh S (CONVERGYS CORPORATION) 0 Reputation points Microsoft Vendor

The issue is, when a call is routed though SBC to teams, Microsoft is replying with an error message (which is seen on my SBC) as below:

(Error screenshot attached.). I have also attached a reference screenshot of my transport TLS settings with sensitive data hidden.

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  1. LiweiTian-MSFT 13,910 Reputation points Microsoft Vendor


    According to the documentation, Q.850, cause=79 represents "Service or option not implemented, unspecified".

    The typical scenario is a service is not implemented.Reports a service or option not implemented event only when no other cause in the service or option not implemented class applies.

    Please refer to SBC connectivity issues for solutions to SIP options issues or TLS connection issues.

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