close correctly Netmeeting fron dos shell

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I've this issue...
When a pc close his session and NetMeeting is still connected to a
Gatekeeper, the de-registration procedure to the GateKeeper fail !!
I need to close correctly Netmeeting when i do the shutdown.
There is a procedure to close correctly Netmeeting from a schedulated
dos-shell batch command ??
(for me is ok only the sintax ... example : conf.exe exit !?!?!? )
Thx


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