Send Messages to Other PCs over LAN on windows

First let’s see how it works on the versions of Windows upto XP SP2

It’s really easy, all you need to do is follow these steps:

1. Run command prompt (Windows Logo Key + R, then type “cmd.exe”).
   

   Running Command Prompt

2. Type net send x “Your message goes in here between in quotes”, in this command, replace the “x” with the username of the PC on your LAN to which you want the message to be sent. And hit Enter.
   
   

   How to use Net Send command

   If the user is on-line, your message will be sent or else an error message would appear.
3. You can also send messages to ALL THE PCs connected to your LAN at ONCE! To do that just type this command: net send * “Your message here!”
4. The star(*) in the above command tells cmd to send the message to all the PCs which are connected to your LAN rather than specifying one (including your PC also) :D