2015-08-22 - Midnight - NEVER MIND. I've just started deleting every file possible on my hard drive in the hopes it will somehow let me boot from USB or DVD (neither of which it has so far recognized). Windows 10 very persistently wants to take over and is the only OS choice offered in the startup options, which, incidentally, are accessed by tapping the Esc key during bootup. Resetting, restoring, reinstalling, recovering, every possible choice offers nothing but Windows 10 as a target OS. I'm about ready for the trusty ol' chainsaw.

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I really want to like Microsoft, but gee--they make it so hard sometimes.
My 8.1 HP laptop (purchased new a few months ago) got a Windows update that suggested I upgrade to Win10. So, like an idiot, I did.
Everything seemed to work sort of okay for the first couple of days, but then I got stuck in the infamous reboot loop. I couldn't get to a login screen but about twice in 5 days. And it would take hours and hours (days, even) of the circling dots until a login screen would unpredictably, miraculously appear.
When I was first able to log in, I changed the BOOT settings to boot from the HD last since I have a Macrium image from about a month ago on DVD and an 8.1 recovery flash drive. But the machine still wouldn't recognize either one. And naturally I had to reboot to learn that and get stuck in the loop yet again. Grrrr...
The next time I could log in, I told Win10 to roll back to 8.1. It fussed around with that for quite a while, then restarted a couple of times, saying "Working on it" or "Finishing up" or some such folderol. But then it restarted one more time and the message said "Undoing changes."
What the hell?!?!? I guess that last restart triggered the Win10 upgrade again. Just shoot me now.
So, I'm back in the reboot loop, but I figured out how to get to Cmd with Admin privileges. Using that to look around the drive, though, I couldn't find a lot of things I thought should be there. For one, the WINDOWS.Old file that is used to roll back from Win10. Theoretically, it seems.
Long story short (or not really that short--sorry!), I followed the bunny trail to TestDisk and ran some things. I've got the log file here on my ancient, creaking XP and will paste it in the next post, if possible, or attach the txt file if not. I'm afraid I'm not totally sure what all I did, though. I know I did 'P' with whichever folders I could access, but did so more than once--so some of the log file might seem confused or redundant. Like me, alas. Blame my ADD...
I suppose the last-ditch recourse would be to wipe the disk & do a fresh install of 8.1 somehow. But, if someone can decipher the log and kindly give me assistance with how to recover from this debacle, I'm more than willing to learn & try anything.
I'd be most beholden--
Jeanine