We've tried to find a solution for messaging between Win XP/7/8 with Terminal server support. Finally stopped on http://messenger.softros.com
Scripts and msg.exe syntax is a rocket science for users in our network.
I upgraded to 8.1 thinking it would make it better, and boy was I wrong. Sure, the start button is back, but all it does is bring you to the tile window. That is what the windows button on the keyboard does... I installed an aftermarket program that gives you the classic start button.