tried to install sp3 stalled at end. went to ms help (chat) got overseas support. i was told that one care was responsible for the sp3 install problem. then told to turn off onecare. i asked how and the ms tech person did not know because "microsoft has many divisions" after this experience and reading about the pain that one care can cause with sp3, i wonder why i should subscribe. he had me go to msconfig to stop onecare loading. his suggestions did not work after 1 hour i gave up. where is onecare support located ?? If its an overseas group, i think i'll pass given i have had no luck with that support team
I suggest that you might consider uninstalling OneCare before trying to run the SP3 update, though that should not be needed. I also believe that the tech you spoke with regarding the SP3 problem was incorrect that OneCare was the cause of the problem.
I recommend that you contact support for SP3 once again and perhaps you will get a more knowledgable tech this time.