>How do I eliminate the ability of a user to start multiple instances of my distributed foxpro program?

There have been various threads about that subject. Among them, various opinions have been expressed.

If applicable, you may want to try to detect that at the icon level so a small C program can switch to the Visual FoxPro application if it is already loaded or load it.

The most common way has always been to use FOXTOOLS or a DLL call to detect the other instance in the main setup program.