I logged in using another username with administrator's priviledge and ran,
control userpasswords2 to get to the user accounts. I then reset the
password, by leaving it blank, but when i rebooted it didn't work.
If you can log in using another account with admin rights then you should be
able to view the account properties of the administrator account. Its likely
that "Account is locked out" is ticked, clear that. Make sure that "Account
is disabled" is cleared at the same time.