2 airports at 1 wireless modem problem!

[msslife]

I have a very odd issue I cannot solve.

I have a wireless network set up at my home. I have two laptops that were both working fine on the network at one point. Laptop A still works fine, thus the network is working. Laptop B cannot connect to the internet via this network but the airport connection on that machine is completely full.

In my system preferences > Network Panel I am able to see the green light suggesting that I am connect to the network and that I am also connect to the internet via this airport.

It is also worth noting that the same machine works fine connecting to the internet at my office via the airport there as well as other airport networks.

I am at a loss because the fact that laptop A works on the network rules out the network as the issue and the fact that laptop B works on other wireless network suggests that the settings are correct. Both machines are running the same OS 10.6 ( latest updates)

I have the correct password entered. I've even removed the airport card and re-inserted it. Any additional suggestions?

If I closed the connection in A the internet will work in B

[Coprolite]

Have you checked the IP addresses? After you turn off the connection on A, B starts working. What happens if you try to turn A back on while B is still connected?

Is this a wireless modem or is it just a wifi router?