One Web Site Won't Let Me Connect Via Airport



I work at home and most of my work is done in Filemaker Pro. As a result of this I often refer to a web site, for help and ideas. For ages it was fine and suddenly although the rest of my internet and e-mail connections are fine, I can't get on to this one web site.

At first I thought that my IP address (although dynamic) or DNS settings were the problem but then after exhaustive testing I plugged my laptop straight into the router (via Ethernet) and hey presto I could get onto the web site again.

This meant that it was something to do with my Airport express wrieless network, I've been checking various settings on my airport admin utility (i.e changing ip address range from to 192.168 etc) but nothing has happened.

I don't understand how and I don't understand why, please can you help.