using the following command
msg /server:pcname username message
server stays as is. pcname is the name of the pc you are sending to. user name is the name the user is logged in under on that PC. message is obviously the msg u want to send.
you will also need to change a setting on the receiving computer by using regedit.
the following registry key must be activated (as described by Consoles above):
Name : AllowRemoteRPC
Type : REG_DWORD
Value : 1 (the dafault is ‘0’)
(not tested myself: need to verify)