Messenger Server: port 1493, 1542, 1863, 1963, 80 TCP and 443 TCP 

File Transfer/Sharing Folders: local: 1544 and 6891 - in fact 6720-65535 TCP from one source 

Messenger Update: remote: 80 local: 1457 

Remote Assistance (If available): 3389 TCP  

Audio: local: , 1556, 11771, 13803 and generally 5004-65535 UDP  

Remote Desktop and whiteboard: local/remote: 389, 522, 1503, 1720, and 1731 Launching Games: 80  

Video Conference: TCP 9000-9999, 5004-65535 UDP + 80 

Sign-In: remote: 443 local: 1484, 2400  

Disable File Transfer :6681 , 6900