Home Forums Networks & Cross-Platform Networking iChat AV won't connect

If all the right ports are open as it's explained in the link above you may want to try changing this port. I have had some success with it, some that try it don't.

You can also goto Home>Library>Preferences>com.apple.iChat.plist and drag it to the desktop. Start iChat and see if it makes a difference. if not there are other plist file to restore.
com.apple.iChatAgent.plist
com.apple.iChat.SubNet.plist
com.apple.iChat.AIM.plist
com.apple.iChat.plist
Try them all see if it makes a difference?