This is how to activate your Windows client or server in your enterprise environment.
First run PowerShell as administrator.
At the PowerShell prompt enter your KMS server
slmgr.vbs -kms server_or_ip
Now you just have to for an activation.
That's it, your Windows machines should be activated. If you run into any errors I would suggest checking that your PowerShell session is running as administrator and that you put in the correct KMS server address or IP.