Credit: TP (MVP)
Taken from: Technet Forum
You may uninstall license keypacks, reduce the number of install licenses, etc, using the Remote Desktop License Server WMI Provider. For example, if you just need to reduce the installed count of one of the packs from 30 to 25 you could use the RemoveLicensesWithIdCount method. Below is the documentation for the Win32_TSLicenseKeyPack Class:
Here are the basic steps for this example.
1. Get a list of installed keypacks. Open a administrator command prompt and then enter the following commands:
wmic /namespace:\\root\CIMV2 PATH Win32_TSLicenseKeyPack>keypacks.txt
notepad keypacks.txt
2. Let's say you look at the keypacks.txt file and see that the keypack you want to modify is KeyPackId 3, and that you want to uninstall 5 licenses. In that case you would enter a command similar to this:
wmic /namespace:\\root\CIMV2 PATH Win32_TSLicenseKeyPack CALL RemoveLicensesWithIdCount 3,5
Another example, say you want to uninstall the keypack (id 3 in our example). Instead of the command in step 2 above, you would enter a command similar to this:
wmic /namespace:\\root\CIMV2 PATH Win32_TSLicenseKeyPack CALL UninstallLicenseKeyPackWithId 3
An alternative to the above is to Deactivate the licensing server, uninstall the RD/TS Licensing Role Service/reinstall the Role Service, Activate, and install your license pack(s) again. This wipes out the license server database and recreates it. You may need to contact the Clearinghouse if you get an error when re-installing your license pack(s).