Microsoft has the instructions on their website to enable Internet Connection Sharing on a network connection, for use in a home office or when the two computers or machines are wanting to be linked up. Firstly, click Start, then Control Panel, then double-click Network Connections. Click the local area network (LAN) connection or click the dial-up networking connection that you want to share (the one that connects to the Internet), and then under Network Tasks, click Change settings of this connection. On the Advanced tab, click to select the Allow other network users to connect through this computer's Internet connection check box. If this is a dial-up networking connection, and you want the connection to be automatically dialled when another computer on your network tries to connect to the Internet, click to select the Establish a dial-up connection whenever a computer on my network attempts to access the Internet check box. If you want to permit other network users to enable or to disable the shared Internet connection, click to select the Allow other network users to control or disable the shared Internet connection check box. Under Internet Connection Sharing in Home networking connection, select the connection that connects the computer that is sharing its Internet connection to the other computers on your network.
