lost all admin privlages

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i am currently working on a computer with four admin profiles and i
started to clean up the services and other startup items, i realized
it didn't have sp2 on there for xp home, i installed all updates and
then i lost all admin privlages on all four profiles. I tried a
system restore and that didn't work, i also rebooted in safe mode
through the admin account to delete the other users and set up a new
one and i can not even get into the access area, control panel is gone
from the start menu, everyhing. I have run three spyware programs.
Nothing... What can i do to get back admin privlages?? I don't have a
2000 or xp disc to repair or format and reinstall. Anyone out there
that knows anything please help!!!!

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