I’m sure you had to install Lync 2010 at least once from the evaluation version (LSEVAL).
After a while (180 days, if you insist), you’ll have to ‘upgrade’ to the Production version. No re-installation needed, just follow these instructions:
1. Using Lync management shell, run the following command from the path of the Lync server installation:
msiexec.exe /fvomus server.msi EVALTOFULL=1 /qb
2. Using Lync management shell, run:
That’s it. Run this command on every Front-End Server, Directory Server and Edge Server you deployed using the evaluattion media.