If you use NET SEND * and NET SEND /DOMAIN:NAME, only authenticated users on the local subnet that belong to the specified domain will receive the message. You won't have to check to see who all is authenticated first.
You can check the sessions under shared folders or you can download netwatcher:
http://www.pcworld.com/downloads/file_description/0,fid,6992,00.asp>From the console of Windows 2000, how do I list all of the users that are authenicated? Is it then possible to send those users a message (such as "server will go down in 10 minutes")?
.·*´¨)
.·`TCH
(..·*
010000110101001101101000011000010111001001110000010011110111001001000010011101010111001101110100
"When the debate is lost, slander becomes the tool of the loser." - Socrates
Vita contingit, Vive cum eo. (Life Happens, Live With it.)
"Life is not measured by the number of breaths we take, but by the moments that take our breath away." -- author unknown
"De omnibus dubitandum"