CAVS Scheduler & SBS 2003

I have CAVS installed on my SBS 2003 machine & I find that the scheduler won’t run. I installed CAVS under a user that has admin rights on the machine & I can see the installation if I log in as Administrator, so I don’t think it’s an issue with the way it’s installed. I have the scheduler set to run a scan at 4am every day, but it never runs - so far the only way I have been able to scan is to log in & run it manually. I can see that cavasm.exe is running as a service under a local system account, but how is the scheduler run? Is it part of cavasm.exe or is it a separate application that is launched when a user logs onto the system? If it’s the former, then there seems to be an issue with it, but if it’s the latter then maybe I can just use the Windows task manager to launch the scheduler (or run a scan) at the required time. Any advice would be appreciated. Thanks.