That doesn't sound right, I'm sure you can create an invisible window and still have it respond to WM_QUERYENDSESSION.

Some Googling later...

Message Only Windows

In reply to Re: Re: Re: "background" perl processes on Win9X - how to avoid that "Perl - please close this application" on Windows Reboot/Logoff? by EdwardG
in thread "background" perl processes on Win9X - how to avoid that "Perl - please close this application" on Windows Reboot/Logoff? by Anonymous Monk

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