So, you got a PC and someone decided to put a hacked version of Windows 7 on for you
or maybe you installed a DVD off the internet that has pre-cracked your software?
May be you just want to go legal BEFORE upgrading to Windows 10??
Whatever your reason, this is how you do it 🙂
Click on the Start Button and type: CMD (into the ‘Search programs and files’ field in the Start Menu)
The Start Menu will show ‘CMD.exe’,
Right-click the CMD.exe file and select Run As Administrator.
In the CMD window, type: slmgr.vbs -ipk <type your product key here>
To activate windows after changing the key, type: slmgr.vbs -ato
All Done 🙂