Short version of what I'm trying to do is sync my Outlook files from local hard drive to my network drive at work, and I want to try and use robocopy (and a Scheduled Task) to do this nightly. At ...

Just exclude them in your robocopy command. It's what I do when I'm copying from the root of one drive to the other. i.e. robocopy /XD "*System Volume Information*" *RECYCLER* *MSOCache* ...