>Hi Martin
>
>I have already tried but it does not work
>
>my alfa.h is
>

>#DEFINE compila .T.
>

>
>
>In main program I have insert
>
>

>_include= 'c:\alfa.h'
>

Doesn't work that way - _include is consulted when you create a new visual class (or form, formset), and used as a source for the class's header file if you didn't specify one. But you can't add them afterwards in this way. Also, doing anything about header files at runtime will have absolutely no effect - header files are something that has to be set before compilation. So, setting _include in the main .prg will set _include for the rest of your VFP session, and will be used in any visual class you create before you quit, but it will do nothing to classes that already exist.

Another way to set _include is in the tools/options/File Locations/Default Include File. Don't forget to click "Set as default", or else it will also be for the duration of current VFP session.