As the guys from Lifehacker pointed out, if you are using the “Windows 8 Upgrade Assistant”, you are all set. But if you had a legitimate previous version of Windows and you mistakenly formatted the hard drive, moved to a new drive (e.g., Solid State Drive) or if you installed one of the “Previews” or “Windows 8 Enterprise RTM” not knowing that these versions of the operating system cannot be upgraded to Windows 8, you cannot do the “Custom” install, even though you may still have the product key sticker on the side of the PC. You’ll be able to do the installation, but you get an error 0x8007007B or error 0xC004F061, saying that the product key can only be used to upgrade (“The Software Licensing Service determined that this specified product key can only be used for upgrading, not for clean installation”). Now apparently there is a workaround that fixes Windows 8 activation problem and makes possible to perform a clean install of Windows 8 using the upgrade media without a previous version of Windows already installed in your PC.
How to fix Windows 8 activation
Once you are back into the OS, try to run the Activation utility as you would normally do and you should be able to do so without any errors.
I haven’t tried it myself, but many online articles are claiming a success with this method. If you happen to be in a situation where you have to use this method or if you already done it, let us know whether you were successful. Source GuidingTech via Lifehacker All content on this site is provided with no warranties, express or implied. Use any information at your own risk. Always backup of your device and files before making any changes. Privacy policy info.