Locked out ot laptop

[Kkbc05]

Hi, I need to fix a laptop.
It was on windows 8 and has had a recent update.
Now it will only me log in using the Microsoft account . Cannot recover the password for this account.
I've tried all the advanced options and also booting by USB. I cannot bypass this! How can I get to log in via the local account? I'm really stuck, other than replacing the hardrive I don't known what to do?

[#2]

So currently you're on Windows 8 or Windows 10?

If on Windows 10, do you get 'Let's finish setting up your device screen'?

If yes, you can select Continue with limited setup there.

[#3]

Hi,

Not helpful I know (brother in-laws laptop), I believe it's Windows 8, not 100% sure what updates have taken place, they "think" it's updates to Windows 10 - it would have been an auto update as he's not technical.

No option to finish the update, literally boots to the log in screen which is the Microsoft account login linked to an email they cannot reset..

I've changed the boot sequence to boot from USB using Windows recovery but it still boots from HD. I've attempted booting in safe mode and booting to cmd, but everything I attempt asks me to select which account- only lists the one linked to ms account and then prompts for the password. 

At the moment I think my only option is to remove the hardrive, put it into a caddy to copy the documents he needs, then format and do a fresh install.