Can't Connect to Network/internet


I have an iMac and iBook connected to an Airport Extreme (upstairs) and boosted by an Airport Express (downstairs). I connect to the Internet with 1.5MB DSL.

I can connect to the Internet and my personal network with no problem using my iMac. However, my connections are shoddy with the iBook.

Typically, I show a 4-bar connection on my Airport signal icon and usually I am just a few feet away from my Express. I connect to the Internet half the time, but even when I do I cannot navigate to new pages or websites.


Thank you,
Eric L.