What are the IPV4 settings for the Xerox and your computer?
Using a different browser was a good idea - might want to try a different PC, disable the firewall (sometimes a program like Norton 360 will block unknown IP addresses).
Make sure you aren't using http in front of the address, just put in the ip address as is (ie: 192.168.1.200) and make sure you are putting the ip address in the address bar and not a search bar - I have seen that happen.
If none of that works, I would use a direct connection from a pc/laptop to the Xerox machine with a crossover cable. You would have to give the pc a temporary static ip but that would take the router/network out of the equation.