Webcam not broadcasting

Hello,

I have installed a webcam on my laptop. When I am sending an invite to my friends, they are unable to view it as nothing shows. When they turn on their webcam, I get their invites but even after waiting for a long time, nothing broadcasts. A message comes 'webcam not available' or something like that. These problems dont occur when I use the webcam on my desktop. All drivers hv been properly loaded. In the offline mode I can turn the cam software on and cam view myself. However i cant broadcast it when i connect using yahoo messenger. Pls help.

Regards.