Windows Server activation via KMS

Nothing is more fun that finding out a production server has not been activating via KMS like it was supposed to be doing.  Imagine my surprise logging in and seeing a “Windows is not activated” message.  Re-entering the correct kms setup didn’t solve it; in fact, it didn’t even send a KMS message to the server.

It turns out the server was in MAK licensing mode.  I found that out by running the command “slmgr /dlv” in an elevated command prompt and seeing VOLUME_MAK in the description.

In order to get it activating in KMS correctly, I had to do the following (again in an elevated command prompt):

  1. Get the default KMS host key for the correct operating system from Microsoft.
  2. Run “slmgr /ipk host-key-from-Microsoft”
  3. Run “slmgr /skms your-kms-server-address”
  4. Run “slmgr /ato”

At that point the server should be activating normally via KMS.