I've used DvD Flick for over a year. No problems, love the program. Just recently, when I load it, it flashes the opening screen then goes back to desktop. When I try to start it again I get a Windows error message, "Windows cannot access the specified device, path, or file. You may not have the approprate permission to access the item." It's not in the task manager - apps or processes. I've re-downloaded, removed, re-installed several times - no good. Did a search in forums, found same type of problem 4 yrs old with no solution. DvD Flick website forum is down.
Try looking for the application data folder (it might be hidden under 'View' in folder options) and delete the DVD Flick folder before installing. For XP: %username%\application data\DVD flick Failing that, you might have a Restore point you can use that predates the problem. I don't think DVD Flick is supported now.
Update: I had installed uTorrent a few days before trying DVD Flick. I removed uTorrent and guess what? 2 programs that had stopped working suddenly came back to life!!