Mac User Information
Install your network card and cable if you haven't already done so, being sure to follow the instructions provided by the card manufacturer. While a modem can be used to connect to a network, it is not the same as a network card and should not be plugged into the network jack in your room, it will not work.
Make sure the network cable is not a cross-over cable. If you need a network cable, you can purchase one at the Bay Tree Bookstore. Take into consideration the location of your computer so that you can determine the proper length for your cable.