I was attempting to do this very same thing this evening when I came across this link...
http://windows.microsoft.com/en-us/windows-vista/Using-ICS-Internet-Connection-Sharing
Enabling ICS
To enable ICS, on your host computer:
- Open Network Connections by clicking the
Start button
,
clicking Control Panel, clicking
Network and Internet, clicking Network and Sharing Center, and then clicking
Manage network connections.
- Right-click the connection that you want to share, and then click
Properties.
If you are prompted for an administrator password or confirmation, type the password or provide confirmation.
- Click the Sharing tab, and then select the
Allow other network users to connect through this computer’s Internet connection check box.

Note
The Sharing tab will not be available if you have only one network connection.
4. If desired, you can also select the Allow other network users to control or disable the shared Internet connection check box.
5. Optionally, to allow other network users to use services running on your network, click
Settings and select the services you want to allow.
When you enable ICS, your local area network (LAN) connection gets a new static IP address and configuration, so you'll need to reestablish any TCP/IP connections between your host computer and the other network computers.
To test your network and Internet connection, see if you can share files between computers and make sure each computer can reach a website.
**** NOTICE THE SHARING TAB WILL NOT BE AVAILABLE IF YOU HAVE ONLY ONE NETWORK CONNECTION.
MUCH TO MY DISMAY!
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