Registry Utilities – You should be backing up your Dreamweaver registry entries including your site definitions. Unfortunately, the capability is not built into Dreamweaer. The good news though is that there is a utility to do this for you from Corey Eiges.
The time to check this out is now, if you wait till something goes wrong, you are too late so get on over there and download this guy. [Matt Brown's Radio Weblog]