cant voice chat any suggestions?

im in the middle east, my wife is in USA. we use MSN Messenger heavily to communicate everyday. yesterday she came up with a virus and i had her reformat c: and restore a ghost of the original setup. she then removed Messenger and downloaded and installed the latest version. but when we try to voice chat i get a message that her computer is not configured for voice communications. she ran the setup wizard and can hear her voice through the mike in her headphones. the question is do you think this is a windows problem, a soundcard problem or does it have something to do with the cable modem? any help would me incredibly appreciated.

the puter at home is : p3 866, 128mg pc133 monster m80 soundcard, diamond v770 riva 32mg vid card 30gig hd on a gigabyte mobo with cable modem, nic and phone modem installed. no exclamation marks in device manager. if you need anymore info just ask. thanx in advance :(

It sounds like a problem with windows. Have you checked all of the menus under options or prefrences? Maybe something didn't get turned on. It sounds like a problem with windows.

On a tangent...doesn't msn messanger use a copy of netmeeting with a new face?

Did she reinstall her sound Drivers after the format?
Probably but you never know. just a thought.