VFP COM object recompile can’t find include file

I made some simple changes to a VFP COM project prg file the other day, but when I recompiled I kept getting errors that it couldn’t find certain variables (eg COMATTRIB_READONLY which is defined in an include file).

This occurred in VFP8 and VFP9.

To cut a long story short – manually deleted all the fxp files. Opened each prg file and compiled. Then recompiled the entire project to the DLL which worked fine.