I have two computers, both with windows 10 upgraded from windows 7/8. Now I want to pass the older computer to my parents and use the newer computer for myself. With windows 7 I could just take the hard drive and put it in the new machine, it will install new drivers and I can change the activation key to my copy of windows, then I'd be set. How can I do this changing of activation key in windows 10? I don't want to reinstall everything because I have a lot of programs built up on my current installation.