Greetings Darlie,
Depending on what router you're using, simply turning off UPnP support in the router will
most likely stop Voice/Video conversations from taking place (as well as file transfers). If
the router has built-in support for these, it probably won't work.
If you have the Internet Connection Firewall (ICF) turned on, then you won't be able to send
file transfers (unless you specifically open the ports). As well, if you (or whoever is
using the PC) uses a "Limited" user account on Windows XP, with the ICF on, voice/video
conversations will not be possible. If you're referring to Windows Messenger here, there are
also some registry entries you could use to block these features from working (if you're
interested, let me know).
However, if you're referring to MSN Messenger 6, there isn't much you can do to block video
(the webcam function) or file transfers, as they have various techniques (including sending
through the Messenger server itself) to get around "blocks".
____________________________________________
Jonathan Kay
Windows MVP, Messenger
Associate Expert
http://www.microsoft.com/windowsxp/expertzone/
Messenger Resources -
http://messenger.jonathankay.com