I'm really disappointed. I was hoping this was the introduction to a class action suit against MS.
I still have a Windows 8.1 which was turned into a brick when it upgraded to Win10.
Unfortunately, it is my newest desktop, and although I got it to boot, after a week trying, I have been unable to spend the time backing up all my data (or as much as I can) before attempting a clean Win10 install.
I haven't even thought about my workhorse programs that I must reload. That will be so much fun getting them to load and hoping they still work under the ever changing Win 10.
Sounds like you must needs do a complete reinstall by wiping your main HDD and then using the Win8.1 Install CD to start all over again, sorry to say.
Just bite the binky, and do the install, then follow the prompts to call the MS flunkies and repeat various strings of numbers and letters that you will have hopefully written down previously proving that your machine is indeed not a Pirate Machine (Arrrgh, matey!) and you can begin again with a completely blank slate.
Then, first thing, make a COMPLETE backup of your sytem! After that, you should be good to go.
As long as you do not connect to the internet while running Windows(tm), of course. :)