Do other devices work connected to the Router? Try connecting the console directly to the modem. Try connecting a friend's console to the same ethernet cord that your console uses. Try a new cord. If the latter still doesn't work, then something has
happened to the ethernet port on your console and that will require a $100 repair.
Resist any urge at self-repair or any any 3rd-party repair shops. I don't care what your or their qualifications are. If you or they remove any part and replace it, MS will detect a hardware change and issue a console ban from Live and your console will
never connect to Live again. Don't risk it.
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