>Suddenly, for no reason that I know of, .chm help files will not display. Even the VFP help file won't display in the VFP IDE, whether I press F1 or try to invoke the help file from the menu help item. Everything is on the local C: drive. Any help appreciated. TIA.

Tools - Options - File Locations - and make sure your Help File is selected there. VS has reassigned my help file to the online development at times.