Windows 10: New user on computer during update - hacked or bug in update? Cannot log into computer now.

So my son was resetting his computer using the update option from the Windows system menu. He updated drivers, and selected "update and shut down" but during the update portion of the process, he lost control of the computer - somebody else's name popped up and he was not able to log in or stop the process, so he shut the computer down. I turned off the wifi to isolate the machine, and restarted it - the user name on the log into windows screen is not his, and is not a name we recognize at all, and there does not appear to be any way to log in. I have no idea where this new name came from, nor why this time the reset failed to work properly. None of my searching has come up with this exact problem nor have I found a fix that I can do from the locked screen. He swears he did not download anything and states he has never given control of his computer to anyone, ever.


I have no idea how to help him at this point because I am not even sure how to wipe the hard drive and reinstall Windows if I can't get access to the computer at all.


Thanks for any advice you can give me.

:)

 

hacked? - computer logged into user name I never use

Hi gypsycomp and welcome to Tenforums.
This is indeed strange. You are absolutely sure you didn't log into the Admin account to install a program, make some changes to the system, etc.? I don't understand how someone could manipulate the computer, if you put it in hibernation when you left. Did you notice if it was installing any updates? I am just wondering if this Windows Update setting has anything to do with it:


Automatically finish setting up PC after update

• Some updates require you to restart your PC and sign in to Windows in order to finish installing the update, which means you might sign in to Windows and find you can’t use your PC until the update is finished. Windows 10 helps prevent this from happening by allowing Windows to use your sign in info to create a special token. This token is used to automatically sign in after a restart, finish setting up your PC, and then lock your PC to help keep your account and personal info safe.

 

Computer update

For what? And what will this computer be used for?

 

hacked? - computer logged into user name I never use


I got home today and woke my laptop from hibernation and discovered it was logged into the Admin account, which I never use. I am the only one with overt access to my computer.
I use a secured wifi, windows firewall (which may be my mistake), and AVG.
It seems I may have been hacked.
Any suggestions on discovering what may have happened and, if I was hacked, what I can do to protect myself?
Thanks in advance.