Funny you mention that, I've been battling with this application for the past week on Windows Server 2003/2008, and I can't get any of the features to work properly.
Incremental backups fail, scheduled tasks aren't created properly (in service mode at least) and straight copy mode doesn't work. I can only get non-scheduled Comodo compressed backups to work.
It's a real shame, as Comodo usually make decent software and the features of the backup application are excellent for a freebie.
