Mac OSX Infinite Registration Loop

Hello everyone,

I have a Macbook Pro with OSX that I use for work and the person who had it before me created an admin account and then left without telling anyone the password. In order to update software and install software I needed the admin password, so I tried to create a new admin account using these codes in the "-s" command window:

mount -uw /
rm /var/db/.AppleSetupDone
shutdown -h now

Now I'm perpetually stuck in a registration loop and no matter what I try (short of reinstalling the whole OS) the loop won't end. Is there anything that can fix this?

Thanks for your time.