It was yet another big day for Microsoft and the Windows 8 team as the RTM build was officially made available to download for MSDN and TechNet subscribers.
So How to activate windows 8 enterprise Via command prompt with product key.
Step 1: Right click on cmd and select run as administrator
step 2: type SLUI.EXE 3 and press Enter
Step 3: Type your MAK key in and click "Activate"