>Hello,
>
>A couple of times I received email error message pointing to the fact that
>'ShellExecute.prg' does not exist.
>
>In my code I do have calls to execute the ShellExecute (Windows API function) when printing PDF documents.
>So, the ShellExecute is outside of what my program created.
>
>What would cause this error?

Admin, who forbade your exe to shell out? I've seen similar stuff in some environments when, in windows scheduled tasks, the user under whose credentials the task was supposed to run, suddenly lost that right.