[Mike]

Try going to Project > Set Language Tool Locations > Microchip C18 Toolsuite > Default Search Paths & Directories > Include Search Path What this is providing is the location for it to search for all the compiler includes (the ones in between <>)

Mine is by default nothing, but your system may be set up differently. I'm guessing here, but I would try setting C:\mcc18\h as the location.

Good luck,
Mike