Scott,

>I've tried to trap the error and VFP 8 just throws up all over me and then throws me out to boot! VFP terminates!

Have you tried adding SET STEP ON to the code right before the line executes? Sometimes that works better than setting a breakpoint.

Although I'm not exactly sure what's going on here, I have an alternate method of handling a single instance of a form. You can add the following code to the top of your DoForm() function in Utility.prg:

FUNCTION DoForm(tcClassName,tuParm1,tuParm2,tuParm3,tuParm4,tuParm5,tuParm6,tuParm7)
	LOCAL loObject

	*--- If only one instance of this form is allowed and there is 
	*--- already an active instance, just Show it
	IF TYPE("goApp.oForms") == "O" 
		LOCAL loForm
		loForm = goApp.oForms.Get(tcClassName)
		IF TYPE('loForm') == "O" AND !loForm.lallowmultipleinstances
	        loForm.Show()
	        RETURN .T.
		ENDIF
	ENDIF

This code simply sets focus to an existing instance if someone tries to launch a second instance.

Regards,