I have a fully legal Windows 8 upgrade installation that was later upgraded to 8.1 at the Windows store. Way back when, I got one of those free Windows 8 Media Center keys offered by Microsoft. I forgot about it because I didn't install Windows 8 until a few months later. Recently, I ran across it while sorting out old emails and decided to install it. It installed fine and the key was accepted. But after rebooting, Windows comes up as needing activation. I checked the existing Windows key using a keyfinder and it shows that the Media Center key replaced my existing key. And the system will not accept my original key either--the error code is related to using an upgrade edition to make a clean install. It gives me no options for telephone activation. I can't use system restore because it says I have no restore points, even though one was just made a few days ago on Patch Tuesday. (I presume the restore points are tied to the key?) I found out that the free Media center upgrade had a time limit on it, so apparently that's the cause of the problem--although the key should have been blacklisted and not accepted. I have disabled the Media Center upgrade, but it doesn't make a difference. I have a fairly recent backup, so I'm not completely out of luck, but it's over a month old and will require quite some work to save, copy, and redo all the mail, program updates, photos, game saves, etc. since then. (I normally am backed-up daily by Windows Home Server, but I'm away from home for a couple of months.) Does anyone know a way to get my original key to work with this mess?