Today I will be replacing the hard drive on my Mac. I already have everything backed up, however I plan on doing a clean install and getting rid of a bunch of crap I no longer use. On my mac I am using the latest version of Parallels Desktop for the Mac and have one Virtual Machine which is running Windows 10. When I put Windows on this mac originally I loaded Windows 7. Is there anything I need to do to deactivate my key before reformatting? How do I load Windows 10 on it again? (Or do I need to reload Windows 7 and then upgrade to 10? Anything else I should know?