Colin,
I don't think there's any way to do it as cleanly as you can from the form init. I would add a property to the form. I'll call it lDeAbort. In the DE Init put:
IF table doesn't exist
THISFORM.lDeAbort=.T.
ENDIF
In the form Init put:
IF THIS.lDeAbort
RETURN .F.
ENDIF
Returning .F. from the Init keeps the form from instantiating.
>During the DE.Init of my form I check for the existance of a table. If it doesn't exist I issue a message stating that the file doesn't exist. At this point I want to stop instantiation of the form. How do I do this?