But the fact is valid expensive acquired Windows 8 Keys are no longer compatible with Windows 8.1! A circumstance of probably to be compensated by the fact that the user is eternally damned to install Windows 8 and subsequently to install 8.1. Because Windows 8 was already activated, Windows 8.1 should be run well. But here's the kicker: That does not! Windows 8.1 periodically checks the validity of the Keys and then explains the 8.0er Key just invalidated, which is quite inconvenient for the user, since he has no 8.1er Key despite valid license.
Well, why fret. 8.1 is superfluous anyway as Windows Vista, so get rid of it, right? Well not with Microsoft! Windows 8.1 can not be removed and put to one better, it also takes action with hands and feet:
Your Talle Irish? No! Gibts not!
System restore points? Be 8.1 simply destroyed by Windows.
Reinstalling? Windows 8.1 does not see that you like and have denied 8.0!
Factory Reset? And here it gets very funny - even the Windows tries to overwrite 8.1, but it does not succeed in all device manufacturers.
De facto remain in some cases only a complete formatting of the system to Windows 8.1 again to get rid of. Almost like a stubborn virus. Wait a minute, actually just like a stubborn computer virus. Windows 8.1 is a computer threat, so you can only advise: Stay away!