This blog is a collection of my experiences and findings in the Lync world. It is intended to document my experiences, and at times frustrations, with Microsoft's Lync and surrounding technologies. And more importantly...offers a central database for quick reference. This blog is separate from LyncSorted and thus runs its own subscriber feeds.
Every time a call is made to the UM server the following error is logged on the Lync server front end:-
Log Name: Lync Server
Source: LS Exchange Unified Messaging Routing Date: 10/12/2013 09:27:05 PM Event ID: 44022 Task Category: (1040) Level: Error Keywords: Classic User: N/A Computer: lyncFE.lynclab.local Description: An attempt to route to an Exchange UM server failed.
The attempt failed with response code 504: exchum.lynclab.local. Request Target: [DefaultUM@exchum.company.local], Call Id: [9f9a3df33d2544a9a22ff2c17feedcb5]. Failure occurrences: 4, since 10/12/2013 08:36:55 PM. Cause: An attempt to route to an Exchange UM server failed because the UM server was unable to process the request or did not respond within the allotted time. Resolution: Check this server is correctly configured to point to the appropriate Exchange UM server. Also check whether the Exchange UM server is up and whether it in turn is also properly configured."
Make sure the dialplan is configured to use TLS (and not TCP).