Error "The Unified Messaging server is not authorized to accept calls from this SIP peer."

[azeez.raheem1]

Hello,

Any thoughts on this error message from Exchange 2010, will be highly appreciated

ms-diagnostics: 15602;source="XXXXX01.YYYYY.local";reason="The Unified Messaging server is not authorized to accept calls from this SIP peer."

Fault: external calls are not diverting to voicemail

No issues with Internal calls diverting

Both CUCM nodes are UM gateway on exchange

CUCM version: 8.5.1.15900-4
Exhange 2010

Message received from exchange

15:44:07.106 |//SIP/SIPTcp/wait_SdlReadRsp: SdlRead bufferLen=645|1,100,57,1.13369777^172.20.94.5^*

15:44:07.106 |//SIP/SIPTcp/wait_SdlReadRsp: Incoming SIP TCP message from 172.20.94.5 on port 5065 index 28472 with 645 bytes:
[52433782,NET]
SIP/2.0 403 Forbidden
FROM: <sip:907985355373@172.20.250.33>;tag=17449687~87f6953b-7778-4bfa-9076-f68dc52faf84-28041207
TO: <sip:8500@172.20.94.5>;epid=4E9F2BC069;tag=92669396f
CSEQ: 102 INVITE
CALL-ID: aa3d9b00-9ae1b837-4d3f7-21fa14ac@172.20.250.33
VIA: SIP/2.0/TCP 172.20.250.33:5060;branch=z9hG4bK4fc7a3905b4c5
CONTENT-LENGTH: 0
PRIORITY: Normal
SUPPORTED: Replaces
P-ASSERTED-IDENTITY: <sip:MSExchangeUM@XXXXX01.YYYYY.loca>
SERVER: RTCC/3.5.0.0 MSExchangeUM/14.03.0123.003
ms-diagnostics: 15602;source="XXXXX01.YYYYY.local";reason="The Unified Messaging server is not authorized to accept calls from this SIP peer."

many thanks!

[BradEast1]

Check this thread:

https://supportforums.cisco.com/t5/unified-communications/exchange-2013-um-and-cucm-8-6/td-p/2338890

"for info:

The name field in ip gateway definition in MS Exchange 2016 must contains the ip address of the CUCM. Otherwise, an error -

ms-diagnostics-public: 15602;source="EXCH-01.test.com";reason="The Unified Messaging server is not authorized to accept calls from this SIP peer."

p.s. Take tcpdump from Exchange server with "netsh trace" command and analyze it with MS Network Monitor.

p.s. My environment - Exchange 2016 and CUCM 11"

[azeez.raheem1]

Hi BradEast1,

Many thanks for the feedback. The Exchange server have IP address of both CUCM nodes. It's rather strange as other sites, divert to voicemail no issues. I have tried registering phones from this site to one of those Device Pools but end up hitting the same problem.

[azeez.raheem1]

Thanks again for your feedback Brad. We ended up applying a workaround on the cCUBE inbound dial-peer to CUCM. It was pointing to the publisher only but changed it to point to the sub and now diverts to voicemail now working.

I suspect there's an issue with the config of the publisher, on the Exchange side but not very familiar with exchange.