Nephew has a laptop that was given him. The harddrive went out and trying to get Windows 7 installed tell me the product key is wrong. So I went to Dell, only to find the original OS was Vista and the product key on the computer was for Vista. The Service tag I used said there there was no such computer. It's supposed to be a 1750. I believe this is one of Dell's refurbished products.

Can one upgrade to Windows 10 from Vista or does he need to buy Windows 7 upgrade?