does your OS 9 Mac get when it is connected to the Router?
It could be that the IPS's page is cached and it being shown in lieu of being able to connect to the "current" page.
If the IP address of your Mac starts with 169. then you are not receiving DHCP instructions from the Router and therefore do not access the Internet.
You will find the IP address in the TCP/IP control panel.
I'm on OS 9 and connect to the internt through an ethernet connection with two other machines. Occasionally the internet stops responding and it can be fixed by logging out and in again on the ISP's connection status page.
Yesterday this happened and the other two machines reconnected to the internet fine, but my machine is still unable to retrieve pages or pick up emails. I can connect to the ISP's page fine (22.214.171.124), so the cables and network is working, but no webpages work.
I've re-entered all the internet settings (IP address, subnet mask, router and name server addresses but nothing seems to work.
Any ideas (apart from get OSX)?