So my basic facts... I bought 3 fully legit Windows 7 Retail keys a few years back when first starting college (which has gotten dragged out, been trying to go back part time to finish a degree but am an adult with work and other things), not long ago I used one of them I think to put Windows 10 on some older hardware I have, a Clarksdale era Biostar motherboard with 8gigs ram because my main PC crapped the bed and I just need to edit word files at home and browse/simple stuff. (tho it doens't want to save anything to the BIOS changes despite a battery change, so my attempt to make it see all 8 gigs instead of 3 gigs has been moot) I hated it to the point of tears with 20 crashes a day and sending all my data to microsoft in crash reports I didn't ask it to do and similar as it thrashed the drive for ten minutes to mine data to upload without permission and other insane behavior. It also wouldn't let me deactivate any of the nonsense despite ShutUp10 and similar things, nothing would save. BUT it had accepted my Windows 7 key as totally legitimate for install - just sharing. So I put Windows 7 back on using the first key I had written down somewhere back in Jan just to continue using the darn thing. Even tho i'm still only seeing 3gig i'm at least happy that it's not crashing 20 times a day and doing crazy stuff. I didn't yet activate online because I wasnt 100% sure which key I used and whether it would matter if i'd activated a windows 10 with it (assumed that deactivated the key to work on 7 after maybe?) but wierdly enough.. when I got 90 days into the '120 day trial' using the grace period reset it says "this copy is not genuine". I thought that was wierd because I didn't even ask it to activate, or check, or anything... I wasnt aware MS was backdoor checking your install key before you even ask for activation. I was kicking the can down the road just trying to make it thru this semester without losing data or fighting with my PC anymore, but unless I accidentally used a different win 7 key than I thought I guess it doesn't like being upgraded to Win 10 and then backgraded to Win 7. >_< Is this normal/common/others experience this? I'm just curious in general... I know there are a few 'activation tools' and such but I wasn't sure which to trust or where to safely download from... i'm doubly annoyed that I cant seem to backgrade my paid for windows retail to 7 but my 120 days will run out before the semester will and rather than fighting with a reinstall i'm wondering if it's better to just use some kind of activator for this moment. :- / I've never had to use one in the past so wasn't even sure how they all work..