Microsoft allows to activate Windows 10 using windows 7, 8 or 8.1 product key
Microsoft has finally responded to the user feedback in the form of recognizing Windows 7, Windows 8, or Windows 8.1 product key to activate Windows 10 directly after the installation. Your Windows 10 would be genuine here after even with your old or unused Windows 7, 8 or 8.1 product activation key. Now you can just perform a clean install and then use the key for activation – i.e. no need to perform an upgrade.