Playing VOB files causes annoying windows dialog to pop up

[cord]

I'm using the 4.1.9 client and trying to play "naked" VOB files backed up from a DVD (one I own). Every time I tray to play an imported VOB file, I get a dialog entitled "SageTVClient.exe - No Disk", with a with X in a red circle, the message "There is no disk in the drive. Please insert a disk into drive D:" and buttons labeled "Cancel", "Try Again", and "Continue". Clicking cancel causes the video to go ahead and play, with no further complaints.

How do I make this stop happening? It's very annoying, and not at all acceptable, given that I operate the HTPC with a remote control.

Having any DVD in the drive, even a different DVD lets the VOB go ahead and play without complaint.