GINA on Windows 2000 - WlxWkstaLockedSAS ignored

From: Peter Hesse (PeterHesse_at_discussions.microsoft.com)
Date: 08/16/04 

Date: Mon, 16 Aug 2004 11:45:02 -0700

I've written a custom GINA for a client. The idea behind this GINA is they
do not want to require Administrative access for one user to logoff another
user. So, the GINA overrides WlxWkstaLockedSAS() and displays a dialog
giving the user the option to unlock their screen, logout the current user,
or cancel.

When the screen is locked, and the user hits CTRL-ALT-DEL, they are
presented with my dialog, which is a standard CDialog-derived class run with
DoModal(). On Windows 2000 (this doesn't happen on XP) if you hit
CTRL-ALT-DEL while my dialog is up, they are presented with the standard
Windows Security window, containing six buttons. If they choose Cancel from
this, the screen unlocks and the user is logged in as the user whose screen
was locked.

Is this a known problem, and/or is there a workaround? I tried to implement
a low level keyboard hook to grab CTRL-ALT-DEL on my dialog, but that didn't
seem to work. (I couldn't catch CTRL-ALT-DEL, nor could I stop the Windows
Security window from coming up.

Thanks,

--Peter Hesse

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