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#11
I don't know, which accounts you had in Windows 8.1. However, there must have been an admin account. So in Windows 10, make sure that this account exists, make sure it still (or again) is an admin account and then remove the newly added accounts.
On windows 8.1 I only had one account, and in windows 10 I only have this one account also (signed in with Microsoft account). Both of them are admin, and I did not add any new accounts. I only used one account which is still the only account I have ever used on windows 8.1 and windows 10
Do you have the built-in administrator account enabled? If so, it needs to be disabled before reverting back to Windows 8.1.
The wording of the message you got suggests this is the case.
Administrator account - Enable or Disable in Windows 10 - Windows 10 Forums
OK. I am afraid I cannot assist you, I have not a faintest idea what this could be. The built-in admin account was worth to be checked.
.....Don't know what i'm going to do now
I just switched to local account and I still get the same message......This might be a stupid question, but will it work if I delete the administrator account?
In order to delete your personal administrator account you would have to enable and log into the built in Administrator account.
Here's the root problem - you booted from the Windows 10 install media and "upgraded" to a version of Windows 10 that you were not eligible to receive for free. So, basically you really did a clean install. Since you didn't upgrade via the normal path - from inside your old OS to the same qualifying version of Windows 10 you are now stuck with this reversion dilemma.
If I were you, I would make a Macrium Reflect Free image of what you have now and make a Macrium Reflect Free rescue disc that you verify will boot because you start messing around with deleting all accounts other than the built in Administrator account and you might find yourself locked out of your Windows 10 altogether.