Connecting XBOX360 to Live via Wireless Laptop to LAN?

I have an XBOX 360 and 2 laptops. Xbox 360 was previously connected to Laptop A. Wireless conection was configured to share internet connection and this allowed the XBOX to connect to Live through the laptop. Recently, I have tried the same setup with my brothers laptop, Laptop B. It worked the same. However, my brother found some Malware and we restored his computer to factory settings for it to work. I went to reconfigure the laptop the same exact way again and it no longer works. Live Diagnostic run on the XBOX indicates an insufficient MTU. Connections show positive for network and internet but not live. I manually adjusted the MTU to the windows XP default in the registry. (1460) Problem persist. Any ideas on how to make this work? My brother just got his own XBOX and he cant connect to live.Connecting XBOX360 to Live via Wireless Laptop to LAN?
I have done this with my laptop before, here is a link i used to do it.





http://www.youtube.com/watch?v=UgbX5gM56lE%26amp;feature=relatedConnecting XBOX360 to Live via Wireless Laptop to LAN?
I would highly recommend you invest $20 and buy the cheapest wireless access point, router, or bridge at your local electronics store. Use a laptop or PC to configure it to connect to your wireless network. Then plug the Xbox360 into (one of its) LAN port(s).





If it's a router, disable DHCP (automatic address assignment).





This will solve all your problems and provide a much more reliable Internet connection for the 360.





I bought an Airlink101 Access Point model AP431W from Fry's Electronics for about $15.