Why can't I activate Windows?
In this page
You updated to Windows 8.1 or Windows 8, but didn't have a previous version or the correct edition of Windows installed (error 0xC004F061)
A different version of Windows or product key might have been used as part of a repair
One copy of Windows might have been installed on multiple PCs (error 0xC004C008)
Counterfeit software
Used PC
Hardware changes
If you received a message saying that Windows couldn't be activated, here are a few reasons why it might not have worked, and some things you can try to fix the problem. For more info about activation errors not listed on this page, see Get help with activation errors.
For additional help with the activation process, contact support.
You updated to Windows 8.1 or Windows 8, but didn't have a previous version or the correct edition of Windows installed (error 0xC004F061)
If you see error 0xC004F061 when you try to activate Windows 8.1 or Windows 8, it means one of the following:
You're using a product key to update to Windows 8.1 or Windows 8, but a previous version of Windows wasn't installed on your PC. To update, you need to have Windows 8, Windows 7, Windows Vista, or Windows XP already on your PC.
If you formatted or replaced your hard drive, you won't be able to use a product key to update to Windows 8.1 or Windows 8. You'll need to install your previous version of Windows, and then reinstall Windows 8.1 or Windows 8.
You’re trying to install the Windows 8.1 Pro Pack or Windows 8 Pro Pack, but you already have Windows 8.1 Pro or Windows 8 Pro installed on your PC. To upgrade your edition, you’ll need to install the Windows 8.1 Media Center Pack or Windows 8 Media Center Pack.