Boy oh boy oh boy
Once your CHIP has been detected, when you do the connectivity test it will say
"X box live not found"
(all other things, ip/dns etc found and sorted in green)
IF you had a chip and ran X Box live, it 'updated', let u play and then when u tried later it wouldn't, then u've been zapped and the x box live error is the CLUE/RESULT
IF you've never managed to connect then u have a tech support issue that can be resolved by someone who knows about networks and routers - you WILL be assing something up, somewhere
Third scenario, chip fitted, update downloaded, but machine still saying x box live found on connectivity screen, but games not finding x box live, then YOUR CHIP has beendetected, you've been pulled from access to games, and are no doubt on a 'pending' list for your box to be zapped (week/day, who knows) after which you'll get x box live not found.
SIMPLE.