All you need to do is disable ICS.
To disable ICS on a network connection:
1. In Control Panel, double-click Network Connections.
2. Click the local area network (LAN) connection or the dial-up
networking connection that is shared (that is, the one that
connects to the Internet), and then, under Network Tasks, click "Change
settings of this connection".
3. On the Advanced tab, click to unselect the "Allow other network users
to connect through this computer's Internet connection" check box.
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Thanks,
Marc Reynolds
Microsoft Technical Support
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