How to get SyncToy to run as a Scheduled Task on Vista

Hi,

I have been unable to get SyncToy v1.4.0 to run nightly, using Vista's Task
Scheduler. I'm wondering if this is a known issue or if it's due to the way I
set up the task?

I followed the scheduling instructions in the synctoy help. Task scheduler's
history indicates that the task has run successfully, but synctoy's 'last run
at:' indicates that the sync did not run.

Any suggestions on settings in task scheduler to tweak? I've tried various
permutations. (BTW I am using SyncToy as it lets me specify which files to
backup, as opposed the 'Backup and Restore Center' which has a 'file types'
dialog)