Sorry for the confusion. I downloaded and ran the "System Update Readiness Tool (KB947821)". That util reported no errors found.
Just to clarify my original post. My customer wants to install SP1 but can't because there are about 12 updates that won't update. Due to this problem, he's stuck. After trying numerous suggestions, he decided to do the upgrade thingie in hopes that that would fix his problem with the "stuck," stubborn updates. But even the upgrade route doesn't work.
In essence, he's got two problems: The upgrade won't install, and he's got other updates that won't install, stopping him from having SP1 installed.
BTW: TGSoldier, what does the offline update utility do? What's it supposed to fix that differs from the other tools? Thx.