Forwarded numbers only work when called internally

[dhs3_init-R_SIPMOTOR]

Hello,

I've been battling with this problem for a while now and would be happy if someone could provide assistance.
I have a normal IP Deskphone 8038 user with a Programmed key using the "Immediate Forward" Prefix.
If the number is called from another, internal user, then the call gets forwarded to the mobile number normally and the call is successful.
If, however, the number (Deskphone user) gets called from an external number, say, a mobile phone, then the caller hears the message "The number your calling is not available" and the Deskphone doesn't ring. I've checked the classes of service and external calls/forwards are enabled.
Then I've run the motortrace and found out that a "403 Forbidden" and "Warning: 399 " Authentication Failed on INVITE" messages get generated when the caller is an external number.
I've already contacted the provider multiple times and they always say that they've run the tests and that on their side everything is fine.
The provider says it's a PBX problem.

I've run out of ideas and would be very glad if someone could provide help in this regard.
Thanks in advance,

Mark

[haroun]

Hi
did u also managed the Bypass on forwarding : 1

[vad]

Check what happen with SIP trace.
Usually with extenal forward and calls from external numbers exist two problem:
- forbidden transit external-external - you need to check connection COS (connection COS for incoming and outgoing TG).
- NPD for external forwarding - if during transit you use as Calling number (or FROM field) - calling number from incoming call - provider can reject this call.

[dhs3_init-R_SIPMOTOR]

Hello,

thank you sincerely for all your ideas. I've adjusted the bypass on forwarding to 1 and one entry in the connection COS that was sent to 0, I've set to 1. Now it works!

Thank you very much for your help, it is much appreciated!

Mark