New
#1
7 to 10, back to 7, eventually to 10.
Hi. I have a desktop running Windows 7. I understand that one can upgrade to 10 for free, then downgrade back to 7. I also understand that, when upgrading to 10, MS does a hash of the product key and stores it on its server. My question is, if I eventually upgrade that machine to Windows 10, that the product key stored in the MS servers will be good and I won't have to buy Windows 10?
To recap, I want to upgrade from 7 to 10, downgrade back to 7, then in a year or two upgrade to 10, all for free. Possible?