Robohelp for Word 7.0--WinHelp 4.0--Corrupt Word File--how to fix??

Hi All--
I think one of the .doc files in my project is corrupt. When I compile the project in RoboHelp for Word 7, the context sensitive Help (F1) for all the topics in a particular file does not work. However, if I take the project out of RoboHelp and compile it in Help Compiler Workshop--the f1 help works like a charm. Ideally I don't want to ever have to compile this file outside of RoboHelp, but I'm kind of stymied. I can't figure out what is wrong with the file and the error wizard hasn't been exactly helpful. I did however notice that while the Help was compiling that the message 'removing watermarks' came up right after the problematic .rtf was compiled (didn't show up in the error wizard for some reason), but I can't find any watermarks in the file. I inherited this project (the other writer left before I started here) and it's been a while (OK like 10 years) since I last worked with WinHelp (converting to HTMLHelp is not an option) so any suggestions for what I should be looking for would be appreciated. Thanks, Jen