Her er meldingen jeg fikk fra Xbox live: Your network doesn`t have a sufficient MTU setting. Xbox live requires a minimum MTU setting of 1364.
On your pc, go to your router configuration webpage and set the MTU to auto, or 1364 or higher. If that doesn`t work, disconnect your console from the router and connect directly to the modem.
Get help with MTU settings at
www.xbox.com/networkhelp.
Have you corrected your router`s MTU settings, or are you connected directly to the modem?