Vista - Accidentally Removed Administrator Account

Hopefully this is in the right forum, I don't know much about computers.
Anyways, I have a Dell running Vista Buisness 32 that was issued to me
by the Navy. I'm out of the military now and wanted to change around
some of the user settings (some kinda annoying DoD login stuff) but
unfortunately managed to do something dumb. Rather than just modifying
the login screen which I meant to do, I think I removed the
administrator user account.

Before, whenever I wanted to change anything about the computer or
install something, etc, I would get a little message asking "Are you
sure?" and then asking for permission. I would just click okay and it'd
work.


Now, though, when I go to change something (like trying to do a "System
Restore" after my mistake) it comes up with that same permission box,
but is asking for a user name and a password that I don't have/didn't
set up. I don't know if this is because I totally wiped out
administrator controls or it's asking for the infor our IT folk put
into it before (if they did leave themselves an entrance account I
can't get the info for it)

All the changes I made were through the control panel, user accounts
interface.

Any help or advice you guys could give me would be very much
appreciated, the OS still works overall but I can't install anything
new, or download anything, or even use some programs/processes already
installed.

And yes, I know I'm an idiot :P




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m121038