There’s a process on TechNet for upgrading an Evaluation installation of Lync 2013 to the full licenced version, but it fails to mention that the process kills the Front-End server!

There’s some logic to this I guess – we need to stop running the time-bombed version of the Front-End’s executable and replace it with the full release – but the process could be a little more idiot-proofed if they mentioned this, lest you innocently try this during the day. (No, I didn’t, but thanks for asking).
 

Here it is for next time:

Log on to the server as a Local Administrator & open an Elevated Lync Server Management Shell window.

Check to see if you’re time-bombed or full:

PS C:\> Get-CsServerVersion
Microsoft Lync Server 2013 (5.0.8308.0): Evaluation Version

To upgrade this, copy “server.msi” across from the licenced copy of the installation media, replacing the original one in the Eval media. (This will be in the second Setup folder in the installation path: C:\<PathToTheEvalMedia>\Setup\amd64\Setup). As always, it’s good practise to rename the original server.msi before you drop the new one in its place.

Execute the following:

PS C:\> msiexec.exe /fvomus "c:\<PathToTheMedia>\server.msi" EVALTOFULL=1 /qb

Once complete, run Enable-CsComputer:

Enable-CsComputer

Check the version’s updated correctly:

PS C:\> Get-CsServerVersion
Microsoft Lync Server 2013 (5.0.8308.0): Volume license key installed.

Now check your services:

PS C:\> Get-CsWindowsService

Status   Name            ActivityLevel
------   ----            -------------
Running  W3SVC
Running  MASTER
Running  REPLICA
Running  RTCCLSAGT
Stopped  RTCSRV          Incoming Requests per Second=0,Messages in Server=0,Incoming Messages Held=0
Running  RTCCAA          Concurrent Calls=0
Running  RTCCAS          Concurrent Conferences=0
Running  RTCRGS          Current Active Calls=0
<etc>

and start:

PS C:\> Start-CsWindowsService

Hopefully you’ll be back up in no time…

You need to repeat this process on all Front-Ends, Directors & Edge servers. Monitoring, Archiving and other ‘Application’ servers don’t need it. If you try on them, you’ll be told as much – but no harm checking to be sure:

PS C:\> Get-CsServerVersion
Microsoft Lync Server 2013 (5.0.8308.0): No license key required for installed Lync Server components.