Originally Posted by Swag
Long story short, it isn't possible to have the OEM key work again. OEM keys are single-use keys and can only be used on one computer. After erasing the entire Windows installation, it made that specific key invalid. The only way to get Windows 8 to work again is to get another key.
Uh, I don't think that's correct (at least in Windows 7). You can completely wipe the HDD (or have the HDD completely fail, and buy a new, empty one), and you can reinstall Windows on the same machine only
with that OEM key, as long as you reinstall the same edition
(e.g. "Home Premium"). From what I understand, you may have to activate by telephone, but it should work.
Originally Posted by MastrChiefMoe
Hey guys. I purchased a laptop earlier this year which came with windows 8, and after some time using it I just couldn't stand it anymore and had to put windows 7 on it, but before I wiped it clean I used a program to retrieve my product key and now I am trying to reinstall it with the key that program retrieved but for some reason it keeps saying the key is invalid.
The Windows 8 key is only valid for Windows 8. It cannot be used in Windows 7.