I have a MB 12 and want to install windows on bootcamp. I own a license for windows 8 and that was upgraded to windows 10,which has it's own product key. -The license i legally purchased for my computer was a full version of win 8.1 and recently upgraded to win 10. The computer is junk and I won't be using it any longer. Can i somehow deauthorize windows on this one to use on bootcamp on my new MB? I plan on trashing this computer. -If yes, to last then do I install win 8.1 or win 10 on my MB? Meaning the key i purchased is for 8.1 but I now have a key after i upgraded to win 10. Perhaps I'm asking this wrong but hopefully you get the point. Or do I just need to buy an all new product key for windows?