This is the PowerShell code to activate Windows.
$computer = gc env:computername $key = "aaaaa-bbbbb-ccccc-ddddd-eeeee" $service = get-wmiObject -query "select * from SoftwareLicensingService" -computername $computer $service.InstallProductKey($key) $service.RefreshLicenseStatus()
Notes
https://gallery.technet.microsoft.com/scriptcenter/OS-Activation-by-MAK-using-e8a8ad2c
Command line method
slmgr.vbs /ipk XXXXX-XXXXX-XXXXX-XXXXX-XXXXX
slmgr.vbs /ato
List available editions for upgrade
DISM /online /Get-TargetEditions
To upgrade from evaluation to standard
DISM /online /Set-Edition:ServerStandard /ProductKey:XXXXX-XXXXX-XXXXX-XXXXX-XXXXX /AcceptEula