Received new Dell Inspiron 3521 with password already on

Dear whoevercanhelp

My partner just received her new Dell laptop, and when first powering it on was met by recovery failed, then when restarted "other user" login, No idea what the username and password were.

Kept powering on and off hoping it was just a temporary setup problem, then the adminstrator account came up, but couldn't login.

I managed to access the command prompt through safe mode (although nothing else is available in safe mode - just says current user is invalid). I then made a new user through the command prompt.

When restarted this user comes up, but cannot log in and User Profile Service is unavailable.

This is obviously really annoying as it was her birthday present, and since Dell no longer comes with OS discs I cannot fix it with them, plus I don't know the Windows 8 serial number.

I also cannot contact support as the service tag does not work. It does mention if a new computer leave for 48 hours, so far these 48hours have been pretty shoddy.

Can anyone help please?

John