Hi I am trying upgrade to Windows 10 from my Windows 7 Ultimate. I downloaded and tried to install Windows 10 and it failed I got the error message 8007002c-4000d and when I tried to install it again Windows is saying - Windows isn't activated on this pc. use a product key to activate it before upgrading to windows 10. I don't know what my product key is but it shouldn't ask me what it is nobody I know has had any problems like this. Can anyone help me ? Thanks.