I connect my Macbook to a LAN through an ethernet connection. Has worked fine for months. Then today without changing any settings or anything just suddenly stopped working. All the other computers on the network still connect fine. Ive even tried swapping out the ethernet cables but it still wont work. In the network settings panel it has the red disconnected button next to built in ethernet, and says "Ethernet cable is not connected". I'm assuming now that the ethernet card itself is messed up, which is dissapointing since i just purchased this computer in august. any help would be appreciated.