This is how I would recommend setting the internet sharing up without the need for additional hardware, and assuming you are running Windows 2000 or XP.

1. Set up the wireless network in the DI-624, disable its DHCP server and give it an IP of 192.168.0.254.
2. Connect the desktop PC to one of the DI-624's LAN ports via Ethernet.
3. Enable Internet Connection Sharing on the desktop PC's wireless adapter and specify the Ethernet adapter as the interface to provide internet to. This will assign a static IP of 192.168.0.1 to the Ethernet interface and enable a DHCP server on it to assign an IP to the laptop automatically.
4. Join the laptop as a client to the DI-624's wireless network. It should obtain an IP address and settings automatically and be able to access the internet.

If you have a third party firewall on the desktop PC, make sure you configure it to allow any traffic on the 192.168.0.1/24 subnet otherwise it may prevent this from working.

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Jeremy

Marlborough WiFi Project