I occasionally chat to some friends and family abroad who use webcams. However, since I have been using a router, I have been unable to view them because of the built in firewall. Adept came down and opened up one of the router ports and I changed my Yahoo Messenger setting to "firewall no proxies" but to no avail. I have now found the answer! It apppears that newer versions of Messenger can cause all sorts of problems such as this, so I have downloaded an old version from
http://www.zakie.fsnet.co.uk/ChatRoomsStuff/Help/messengerdownloads.htmI no longer have a problem with viewing webcams.