Mac Forums

How can I fix this problem? When i secured my system with entering all mac addresses: taht is my 2 laptops, my denon sound system and my internet radio everything went fine apart from the fact my room mate's laptop now is not authorised to use the internet. Yes we have entered the mac address and it's correct! It keeps saying the netowrk settings are not liek those in the laptop. What can i do?
Yes I am sure it is the right make adress i checked and rechecked...