We are having a strange problem today. We have a SIP trunk from a provider and incoming calls are being dropped after the IVR when attempting to connect to any internal phone. If a you dial a DID that goes directly to a phone you can talk but the call will drop when you attempt a transfer.

The trunk provider tells us that they are dropping the call because according to them we are trying to transfer the call out on the trunk instead of doing it internally (which I really do not understand how that would even be possible). In the CLI I can see the following error when the call drops:

— Got SIP response 500 “Server Internal Error” back from
172.XXX.XXX.XXX:5060

Since that is the IP of the provider I woud assume the problem is on their side but they are insisting Asterisk is to blame here. We are running Asterisk 11.6-cert10 which has been working fine until today with no changes.

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Telecomunicaciones Abiertas de México S.A. de C.V. Carlos Chávez
+52 (55)9116-91161

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