I've read further and you had the idea of using a dummy window for finding out, when the designer is closed.

Well, as my solution uses the project hook, if the form or class is open in the designer, the QueryModifyFile is through, but I attach an Eventhandler, so when closing the class or form designer, the object is destroyed and if I bind to destroy the eventhandler could do something at that point.

Bye, Olaf.