Same Problem
I'm having this same problem. I did a fresh install on my HTPC from Vista 64 Home Premium to Win7 64 Pro, reinstalled DVDFab, and now it won't recognize any disk. The disks play fine in windows, but DVDFab won't do anything. If I hit browse, I can browse into the DVD, but it still won't do anything.
I am accessing the HTPC through remote desktop, so I will try again from the local box to see if that helps.