Yes, I still support Skype for Business Server (thankfully, no Lync at the moment). Last week I had an odd one. During a security updates patching exercise, a couple of Front End servers required a restart.
All expected services came up nicely except for the Skype for Business Dialog Listener service. When I start the service from the services.msc management console, it starts up, then goes into a stopped state.
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This would ordinarily not cause much of a concern, but the monitoring system was chucking out alarms across all the affected Front Ends regularly – each alarm creating a ticket in the ITSM tool.
From an elevated PowerShell command, I browsed to the directory where the DialogListener.exe application was and ran it.
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Client certificate not found or not valid. OK.
Expected Client Certificate not found or not valid – and we have a thumbprint to go on with.
Ran a Get-CsCertificate, but no such thumbprint was found on the server.
I proceeded to check the other affected Front Ends; they had different thumbprints not found on those servers.
Checked the DialogListener.exe.config file and found a thumbprint in it. This was the thumbprint that was displayed earlier when I ran the DialogListener.exe.
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What is going on here? Let’s launch the Skype for Business Deployment Wizard, and check the certificates applied. Got the thumbprint for that and copied into a text editor. Replaced the thumbprint in the config file with this thumbprint. Saved (obviously after making a copy) the file.
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The service did not start after this piece of work.
Ran the DialogListener.exe again and got this:
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Fortunately, this seems straightforward.
Computer Management > Local Users and Groups > Groups
RTC Local Administrators
Added the account used to start the service into the local security group.
Service came up automatically.
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That’s it folks.