My father in law has a powerbook G4. He's been using it for quite some time. Recently, it decided to stop connecting to the net, and even when it will let him browse, it won't let him get his Email (using the Mac mail program). There have been no changes in his email accounts, no changes in anything that we know of in his Mac, and the other computers in the house connect just fine. Any ideas for what could cause Mac Mail to just suddenly refuse to work like that?