Xbox 360 Connection Tests: IP Address
This test verifies that your Xbox 360™ console has a valid IP (Internet Protocol) address.
If your console does not pass this test:
Confirm that there are no other devices on your network with the same IP address.
If you are using a router or gateway, verify that it is configured to assign IP addresses to network devices (DHCP-enabled).
If you are connected to a router, make sure that your console'sEthernet cable is not connected to the router's LAN port rather thanits WAN port.
If you are connected directly to a modem and your ISP (Internetservice provider) requires PPPoE settings, verify that your PPPoE username and password are correct. If your ISP doesn't require PPPoEsettings, remove the PPPoE user name and password settings.
If you are connecting directly to a modem and have replaced a devicethat was connected to your modem with your Xbox 360 console or anotherdevice, turn the modem off and back on before connecting the newdevice.
If you are using a static IP address from your ISP, verify the address with a your provider.
If your console is connected to an ad-hoc network (in which devicesare connected directly to each other), it will probably not pass thistest. If your IP address is assigned automatically and your ad-hocnetwork does not include a DHCP server, this does not indicate aproblem. The test is properly reporting that a DHCP server could not becontacted. Xbox Customer Support does not support the use of ad-hocnetworking to connect to Xbox Live.
If you're using an ad-hocnetwork without a DHCP server and you can't connect to Xbox Live, checka different diagnostic test for the root of your problem.
This comes from http://www.xbox.com/en-US/support/connecttolive/xbox360/connectionmethods/troubleshootliveconnection-testipaddress.htm
Hope i helped you.
Thanks for using ' Fixya ' and have a nice day!!