I had this problem on one of my test PCs, that XLobby was unable to connect to the net. Explorer workes, Skype worked, AV was able to retrieve updates, etc, everything worked except XLobby.
It is a PC which uses proxy, and in IE, it was setup to use proxy server over port 8080. When I set this to "automatically detect settings", all of a sudden XLobby was able to display weather info and news....
Just thought to share it here - someone else might have the same problem eventually.
D.