Net Send to a group of computers

you have to start alerter service also

you don't need any additional software, you can do this through windows...

on the computer you are sending the message from, right click my computer, select manage, select shared folders and right click on it, then select all tasks, send console message. You can send the message to single computers or groups of computers.

With Group Net Send you can send messages to any username or computer name on your network. Just create a message.txt file with the message you want to send (supports CR LF characters). Next, create a usernames.txt that contains the list of all the users you want to send the message to. Configure those files on the command line and press enter, we do all of the work!

 Before ths just check that Messenger service has started.

Regards
Sandeep raj

Net send

Sends messages to other users, computers, or messaging names on the network. The Messenger service must be running to receive messages.

net send {name | * | /domain[:name] | /users} message

Parameters

name

Specifies the user name, computer name, or messaging name to send the message to. If the name is a computer name that contains blank characters, enclose the alias in quotation marks (" "). Long user names may lead to problems when used as NetBIOS names. NetBIOS names are limited to 16 characters, and Windows 2000 reserves the 16th character.

*

Sends the message to all the names in your domain or workgroup.

/domain[:name]

Sends the message to all the names in the computer's domain. If name is specified, the message is sent to all the names in the specified domain or workgroup.

/users

Sends the message to all users connected to the server.

message

Specifies text to be sent as a message.


Notes

You can send a message only to a name that is active on the network. If the message is sent to a user name, that user must be logged on and running the Messenger service to receive the message.

Sending messages to multiple users

Windows 2000 provides several ways to broadcast a message. You can broadcast a message to all the names in your computer's domain (use * or /domain), or a different domain (/domain:domainname). Broadcast messages can have as many as 128 characters.

The /users option lets you send a message to all users who have sessions with the server. Parameters that send to multiple users should be used with discretion.