NBU 6.0MP4 Windows Server 2003.

I have it set so that the catalog backup is supposed to run "After each
session of scheduled backups".
Unforunatley I doesn't run unless I start it manually. I've noticed that
after rebooting the server the
catalog backups run like they're supposed to but after a couple days it
reverts back to not running
as scheduled. Any one else experienced this?