Installing Active Directory services on Windows server 2012 R2 evaluation? Hold on!

For testing purposes I installed Active Directory services & NAP on a single evaluation version of Windows server 2012 R2. Because things were running better than expected I ordered a license to activate the evaluation version and keep using the machine without having to reinstall. It turned out Microsoft didn’t want me to activate. I kept hitting the following error:

Error 50: Changing this windows edition is not supported online for a domain controller.

Searching Google for this error message came with a lot of websites with possible solutions. None of them worked until I installed a secondary domain controller (which can also be an evaluation version) and entered the following Powershell code to activate Windows server:

dism /Online /Set-Edition:ServerStandard /ProductKey:xxxxx-xxxxx-xxxxx-xxxxx /AcceptEula

After a required reboot my server was fully activated. Please note Microsoft does not mention this ‘feature’ in any document as supported, so beware as it can be fixed/disabled at any time. Activate Windows server before installing Active Directory services to be safe.