I can surf okay (but slowly) when I have the Cat 5 cable plugged directly into the MacBook, but no luck with the Airport Express.
After much fiiddling it will come up with a message like, "You appear to be connected to the internet, but we are unable
to find http://www.google.com you may have mis-typed it."
I've put in my IP manually. Subnet mask is 255.255.255.0 Gateway is my base IP but ending in a 1. DNS1 is 203.96.152.4 ,
and DNS2 is 203,96.152.12
At the moment I have turned off all encryption just to make sure that isn't a problem.
Everything will look like it's connecting okay, but I can't surf the web with the Airport Express.
Humm....