ARRIS modem is a phone/hsi modem. What youll need to do is first turn power off on xbox then unplug the power supply from the back of the Arris modem and unscrew the coaxil/cable wire from the back of the modem for about a minute. Then plug in the power cord to the modem wait another half minute then screw in the coaxil/cable wire....wait for the lights to come back on make sure the online light is solid green not flashing and follow the ethernet cable (Looks like a thick telephone wire) and make sure you have that ethernet cable seated/snapped into the ethernet port on your xbox. Then turn the xbox on and do connection test. FINISHED..IF it's still not working make sure you have Internet service from your provider and if using a router bypass it at first see if you can get onto xbox live without the router. If you can with just connected directly to your arris modem without the router involved. If you do want to use wireless contact your router manufacture and or xbox support at 800-469-9269.