Xbox360 & Internet connection sharing

I use ICS with the xbox connected via Ethernet cable to a laptop which then shares a wi-fi connection. Xbox-> Ethernet -> laptop -> wi-fi

This is because a public wi-fi network exists in the building which the xbox cannot directly connect to via it's own wi-fi adapter (requires login via a web page).

As I spend my time between UK and UAE I use a VPN service to download geographically restricted content onto the xbox if I'm in UAE. To do this I share the VPN connection with the Ethernet using ICS.

Problem is that suddenly ICS no longer works either when sharing the VPN connection or the normal wi-fi connection. I can bridge the wi-fi and ethernet with no problems but you cannot bridge a VPN connection.

When trying to use ICS with the Ethernet I set IPV4 to obtain addresses automatically. However as soon as I try to connect the Ethernet IPV4 settings changes on it's own.

I also have a laptop running XP and get the same problem. Can anyone help?

I have tried that but the xbox completely fails to connect even to the laptop when I do that. With auto settings on the xbox connects to the laptop but nothing else.

I have purchased a USB wi-fi adapter then created a home network then attached the xbox to it via it's own wi-fi adapter. Still no joy. I have tested the home network with my iPhone which connects beautifully and can access the Internet from the home network (with sharing the internal wi-fi connection and also VPN).

I think the problem sits with the xbox rather than windows 7. If anyone has any other ideas please let me know.

After turning off the McAfee firewall and real-time scanning everything now works fine. Email has been sent to McAfee asking them for a solution that allows the laptop to remain protected. Just turning off one of these features did nothing. Neither did adding the IP address used by the xbox to the trusted connections.