My problem: A local admin can't install SP3 on an XP sp2 machine.
Details: Where I work, we have employees that are not domain admins. They are (though) part of a group that is local admins on most of our desktop computers. We have a downloaded copy of SP3. I had an employee, that is part of the group that is a local admin on a desktop, try to install SP3, and it said he didn't have permissions and to contact the local administrator. I didn't see any errors in the error logs. We have AD GP's in effect, but I'm not certain what would be over riding his local admin rights to install SP3.