Microsoft Evaluation to Production
So you installed an evaluation edition of windows and when you tried to activate it through the GUI it said that it could not upgrade it to this edition. Well fear not there is a way. The first command to run is
DISM /Online /Get-TargetEditions
What this will do is get the Editions that your OS can be updated to.
For 2016 you most likely will just see two
ServerStandard
ServerDatacenter
Next comes the longer command.
DISM /Online /Set-Edition:<Place Edition Here> /AcceptEula /Productkey:12345-67890-abcde-fijkl-mnopq
Now the system is going to get to 10% and take a while. You can open your task manager and see that the Windows module is running and using a lot of the cpu. Now if you have been waiting more than an hour you can try to close the Powershell window and reboot the server. Note that if the server gets stuck in reboot for more than an hour power it off and turn it back on. Check that the version and activation is good to go. Please not that if it didn’t work start from the Beginning and do it again and it should be fine just have some patience.