I am having similar problems but with a number of added variables :/
It is a terminal on a small office network routed by Netgear FR114P to a Static DSL Broadcast. All IPs are assigned by DHCP to the terminals (4) on the WAN.
I have exhausted every trick and tool I have to establish a connection for that terminal.
I have access to it and from it to every other network computer.
All the other computers have access to the internet and similar software profiles
I can ping the other terminals by name and IP, as well as the primary and secondary DNS.
I have the cleared rules and services settings to default and nothing is blocking its address specifically.
I have tried using Opera 7 browser as well as attempted to update my F-Prot from its regular internet uplink.
I have dumped IE settings and reset to default and rebooted enough times to make me feel obsessive compulsive
I have uninstalled/reinsalled NICs as well as physically removed and substituted different
models to give different mac etc.
What is left ? I like to think that I know whats up but most often its a mystery