Recently, my MacBook (purchased summer of 2007 and running Snow Leopard) stopped connecting to the internet wirelessly. It can connect to the net via ethernet. And it can connect to networks and other computers wirelessly to exchange files, but not to connect to the internet through them. It backs up to my Time Capsule wirelessly without a hitch. This seems like a software problem, not a hardware problem, to me. Any thoughts on why I can't get internet access wirelessly?