TSMsg is a command-line tool to message Citrix or Terminal Server
Sessions on any server within a Domain. 

This utility was written to replace the command MSG.EXE currently
found in the MS Windows Operating System. This utility offers an extra
feature that will be of benefit to all admins - the /SERVER:* switch.
Using this switch, an administrator can message all users on all
Citrix/TS servers with one command or multiple servers with a common
structure e.g. /Server:MySer*. This command can also be used in a script.

This utility is FREEWARE and was written by Warren Simondson of
Ctrl-Alt-Del IT Consultancy, Australia. www.ctrl-alt-del.com.au

Thankyou to the WINDOWS SDK available from http://msdn.microsoft.com/downloads

Usage:
TSMsg [UserName | SessionID | *] [/SERVER:servername | *] [/TIME:seconds] [Message]

  UserName   -   Identifies recipient of the message
                 (NOT case sensitive)
  SessionID  -   [Optional] Identifies Session ID of recipient of the message
  *          -   [Optional] Send message to ALL users on chosen server

  /SERVER:servername  -  [Optional] Specifies the Terminal server containing
                         the user session to send message (default is current).
  /SERVER:*           -  [Optional] Send message to ALL servers for the chosen
                         user/s
  /TIME:seconds       -  [Optional] Time delay to wait for receiver to 
		         acknowledge msg. (Default=120 Max=9999)
  Message             -  [Optional] The message to send. If none is specified,
                         sends a test message.
  /?                  -  This help information.

E.G. TSMsg Bob My test message

This command will message the user BOB on the current TS or Citrix 
Server within the current Domain.

E.G. TSMsg Mary /Server:MyServer My test message

This command will message the user Mary on the TS or Citrix Server
called MyServer within the current Domain.

E.G. TSMsg 5 /Server:MyServer My test message

This command will message session ID 5 on the TS or Citrix Server
called MyServer within the current Domain.

E.G. TSMsg * /Server:MyServer My test message

This command will message all users on the TS or Citrix Server
called MyServer within the current Domain.

E.G. TSMsg * /Server:* My test message

This command will message all users on all TS or Citrix Servers
within the current Domain.

E.G. TSMsg * /Server:MySer* My test message

This command will message all users on any TS or Citrix Server
with a server name beginning with MySer within the current Domain.
i.e. MyServer, MyServer1, MySerdemo.

The freeware version is offered AS IS. Ctrl-Alt-Del IT Consultancy has made
every effort possible to ensure that TSMsg is free of any bugs or errors,
however in no way is TSMsg to be considered error or bug free.
You assume all responsibility for any damages or lost data that may result
from any errors or bugs in TSMsg.

IN NO EVENT WILL CTRL-ALT-DEL IT CONSULTANCY BE LIABLE TO YOU FOR ANY GENERAL,
SPECIAL, INDIRECT, CONSEQUENTIAL, INCIDENTAL OR OTHER DAMAGES ARISING OUT OF 
THIS PRODUCT.