I’ve actually had dreams (nightmares?) lately about Microsoft license activation, believe it or not, as it is such a pain in the ***. Both Microsoft Windows and Microsoft Office can get to the point where they cannot or will not talk to the KMS server and grab a license for one reason or the other. So, this is how to force the issue when you have enterprise versions of this software.
One scenario is where Windows quits talking to the KMS server, goes beyond the grace period and then declares that this copy of windows is not genuine. You can try to activate it, but it will refuse because it is out of the grace period. Of course, it is outside of the grace period because it did not activate, so this causes a bit of a catch-22.
The way to break out of the cycle is to extend the grace period. You do this via the “rearm” command. For example, open a command prompt with elevated privileges and type:
slmgr.vbs /rearm slmgr.vbs /ato
That will rearm activation, thus extending the grace period, and then activate windows (it assumes KMS is online).