The word is "registry" (if it's the word I think you mean).
Maybe someone else will more easily, and better, be able to answer this question (which showed up in my questions). So, here's a link to a quick summation:
Probably, for the person who doesn't know what the registry is, the more important (EXTREMELY IMPORTANT) thing to know is never try to do anything that involves the registry.
If you're getting a message that involves the registry the best place to start may be to go to a site that offers advice about computers, tell someone who is extremely familiar with computers what's going on with your computer; and see if that person can give you an idea of where you may be able to find the best kind of help. (Or, if the problem isn't a big one, and there's some step you could take to help your PC "fix its own problem", someone with a lot of expertise could advise you about that too.)