Okay my sister has a site that we're both working on and we're having some troubles with the frames. I entered the code and got the right.htm, left.htm, and main.htm and it still said that it couldnot find those pages. Any thoughts?

are you sure those are the correct file names and that that's exactly what you have in the code? is it the correct extension (do you have .html in the frameset code?)?