How to notify (inform) users?

Question

Windows Server

Prompt programs or other ways to unidirectionally notify users, ala "The server will be restarted in 5 minutes, close your programs, PS Admin"

Answer 1

Answer 2

shutdown /? - a list of options
shutdown /i - a box with a choice of options
You can display a message with a countdown, and set different options

Answer 3

gpo