Administrator and User ser as power user so I can change or install certain software

In my haste with ac ertIN USER AT MY COMPANY WHO HAS DAMAGED A FEW SYSTEMS WITH PROHIBITED ACTIONS, WHEN HE GOT HIS NEW SYSTEM i SET HIM UP AS A POWER USER, DURING THE TIME I ALSO SET THE ADMIN PASSWORD, BUT MUST HAVE MISTAKENLY SET THE ADMIN PASSWORD AS A POWER USER AS WELL.

so now when I try to allow him or me as admin access to install his blackberry sw, it asks for an user with admin access, so of course I type administartor and my pass and it says the same thing.  I set it as a standard or power user.  

Is there a way to change back to the default or a workaround to make the admin a admin user again rather than power user.