I actually just figured out that the program responsible was Process Monitor from Sysinternals. But it's a big deal because even after I quit Process Monitor, FBackup still won't work until I reboot. I think that should be fixed. In fact, why not ask Oreans to make the dialog box tell you which program it wants you to quit? There's an idea.
By the way, what's in your code that you really need to hide? It's a backup program; it's not like there's some top secret algorithm or something in there that you're depending on nobody reverse engineering. What are you trying to protect exactly? What exactly are you afraid will happen if you release a version without Themida?