Location: On the left
window's Server tab, click 
Site.
Purpose: Allows you to set and modify site messages.
User limit message
Enter the message that you want users to receive when the Max concurrent connections limit (on the Advanced tab) is exceeded.
Exit Message
The server can send a exit message if the client closes the session gracefully (using a quit or close command). Enter the message that you want users to receive when they log off the server.