Event ID: 44022 An attempt to route to an Exchange UM server failed.

Event ID: 44022 - An attempt to route to an Exchange UM server failed.




Event Log Detail:
Log Name:      Lync Server
Source:        LS Exchange Unified Messaging Routing
Date:          1/17/2014 3:26:27 PM
Event ID:      44022
Task Category: (1040)
Level:         Error
Keywords:      Classic
User:          N/A
Computer:      UMServer.mail.com

Description:
An attempt to route to an Exchange UM server failed.
The attempt failed with response code 504: UMServer.mail.com.
Request Target: [DailPlan@UMServer.mail.com], Call Id: [b14da442c54b4467a67cd1a69be059bf].
Failure occurrences: 3, since 1/17/2014 3:10:05 PM.
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.
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.

Solution:

• The above error will occur if the um server (UMServer.mail.com) if you don't have proper certificate installed in it.
• Verify UM service is enabled for the certificate on executing the powershell command - Get-ExchangeCertificate -Server | fl subject,services
• The ceritificate should hold the server name UMServer.mail.com as the Subject Alternative name in it.
• After assiging the certificate to the Exchange 2013 Client Access and Mailbox Server
• Restart the MsExchangeUMCall Router service in Exchange 2013 CAS Server and ExchangeUM service in Exchange 2013 Mailbox Server