Happened to me as well.
We have 2 perfectly fine 3-4 year old Dell laptops that my 10 year old kids use for school stuff, USB accessable items, MS Word and some basic computer games, wireless games & surfing, etc.
Well, I was away, and my wife clicked the upgrade icons on both computers and went through the upgrade process.
I get home, and both computers are basically useless now. The previous software/hardware apparently don't like Windows 10, or they can't run the new software, no idea what the issues are.
Internet slow, incredible freezing programs & lag galore.
The worst part is, this is irreversible.
This was poorly planned & thought out by Microsoft.
Granted, we were planning on getting them a couple of new laptops this Christmas, but the point of this is that there was absolutely nothing wrong with the ones they have been using for 3 years.
Wife was HOT about it, and my kids had some games on there they can't play anymore.
I've upgrade 3 machines to windows 10, and then easily rolled them back to Windows 7. Did the forced update remove the option in the "Backup" settings control panel tab that allows you to roll back the installation within 30 days?