Thanks for your reply. To clarify my question a little, when I comment out the ON ERROR ErrorHandler(...) I do not get the same error message. In my "Main" program file I have several procedure/function calls (ErrorHandler is just one). When I comment out the ON ERROR I get the same general message but instead of "Program ErrorHandler.prg does not exist" I get, for example, "Program CleanUp.prg does not exist" where CleanUp is a function. This will happen for each function/procedure as I comment out each previous function/procedure. I hope this makes sense.

In the meantime, I will be trying out your suggestions.

Thanks again,
Russell