Internet problems

I have WinXP - SP2

I am connected to a Syslink DSL/Cable router along with 3 other computers in
a small office (No file sharing between the computers)

The other 3 (Win2k) machines have no problem with connecting to the
internet, and even if I swap the cables from a couple of the other machines
I still cannot connect.

I get 'page cannot be displayed' errors. I went through the internet setup
wizard, but still no access.

In my ignorance I do not know what to try next as a solution - what should I
do?

WM