How can I send a message to all users?

A. A. Ensure the "Messenger" service is started (Control Panel - Services - Messenger - Auto). To send a message type:
c:> net send <machine name> "<message>"
Or instead of a machine name type * to broadcast to all stations

There are also various GUI utilities, and one of the best is NT Hail at http://www.geocities.com/SiliconValley/Bay/1999/NT_Hail.html

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