Hi Raj,
Yup, tried that too. No dice. I turned it back off when it didn't help, but the account icon at the start screen remained. Maybe it isn't really disabled.
I did some more googling and found a thread at
2BrightSparks (maker of SyncBack) where sync jobs were failing the same way. One of the posters thought it is a Vista Home Premium bug that might be fixed in SP1. Didn't see any references to that error or the Task Scheduler in the update list though.
I'll keep playing with it, maybe I can find a way around it. I wonder if the commandline utility is available in Vista (like XP and Server2003)?
Thanks again, John