>i just looking for some advices to how i can add security to my VFP programs against piracy . Thanks in advance.
If you're talking about hiding any source, very simply, you can compile all the source into the App (from teh project manager) and turn on encryption in the Project Options dialog box.
If you're tlaking about something like: "If you develop commercial applications, you might want to provide multiple levels of your application (depending on what your users paid for), and thereby prevent unauthorized users from installing and running the application..." this is the intro to a recent FoxTalk article that may be of some help. Its free and can be found here:
http://www.foxtalknewsletter.com/ft/FTMag.nsf/WebIndexByIssue/ED4FA4B7F9620AFD852568EF004C250A?opendocument