Cannot get Vista connected to my LAN

Hi all,

I've been having serious trouble trying to connect a Vista PC to my LAN. XP and 7 on two other PC's both work fine. All PC's connect to my broadband router's Ethernet LAN ports. I usually let the router assign IP's, but since that didn't work I tried setting them manually. According to ipconfig/all the correct IP and subnet are assigned to the NIC, but I cannot ping the router or connect to the other PC's on the LAN. Manually setting the router as the default gateway also doesn't work.

What also puzzles me is that the error message I get when pinging the router varies. Sometimes it says "Request timed out" and other times it says "No route to destination"

Is there some trick involved with setting up a LAN in Vista? Is it more likely to be a setting on the NIC itself? I'm a bit stumped here, so any ideas would be appreciated.
 
Some easy things to try if you haven't already. You'll probably want to go back to Automatic DHCP Settings on the Vista system for these tests. What router and model # is it. Do you know if you're router has a limited Pool of IP addresses to hand out for dhcp? Is it enough? Unplug one of your working systems and plug that cable into your vista system. Don't change the port on the router or anything else. This just to confirm you don't have a cable issue or Port issue on the router. Is the router's Link Light coming on? How about on the Vista PC?
 
I replaced one of my existing PC's with the Vista one. Same cable, same port, both were working fine previously. Link lights are up on both sides. The router is a service provider brand, so no clear indication who the manufacturer is. I can confirm that I've connected multiple PC's to it before with no problems.