My customer wants to do direct SIP Trunk with their Lync server 2010. And on the Lync side have setup CUCM 8.5 as a PSTN Gateway ut they have tried
everything and still couldn't get the call through. Neither from Cisco desk phone to Lync clients, nor Lync clients to Cisco desk phone.
CUCM version - 22.214.171.12400-21
Lync version - Lync 2010
Any instructions on how i can troubleshoot this for my client?
Would appreciated your help.