I just tried setting up my parents network for them again after they just
moved. We never changed any settings on their wifi router except the isp
info.

The pc's we hooked up to the wan were able to it the web just fine, my moms
laptop was able to connect with its wifi card but it couldn't access
websites or services by domain name. I could connect to chat clients like
google talk or even ping ip addresses but I couldn't ping domain names or
connect to them via browser.

We also tried connecting another PC to the wireless network. Since we use
mac filtering on the router I made sure to add the mac address of the new
wifi chip. After configuring the settings on that computer (SSID, WEP key)
it was able to detect the network by displaying it in the list. When I tried
to connect to it, it asked for the wepkey which we typed again yet it fails
to connect. It's not a weak signal, the router is maybe 25 feet away and it
shows 5 full bars.

Any ideas clues on what I should do from here?

How do you setup DNS? posting the result of ipconfig /all here may help.

Bob Lin, MS-MVP, MCSE & CNE
Networking, Internet, Routing, VPN Troubleshooting on http://www.ChicagoTech.net
How to Setup Windows, Network, VPN & Remote Access on http://www.HowToNetworking.com
  I just tried setting up my parents network for them again after they just
  moved. We never changed any settings on their wifi router except the isp
  info.

  The pc's we hooked up to the wan were able to it the web just fine, my moms
  laptop was able to connect with its wifi card but it couldn't access
  websites or services by domain name. I could connect to chat clients like
  google talk or even ping ip addresses but I couldn't ping domain names or
  connect to them via browser.

  We also tried connecting another PC to the wireless network. Since we use
  mac filtering on the router I made sure to add the mac address of the new
  wifi chip. After configuring the settings on that computer (SSID, WEP key)
  it was able to detect the network by displaying it in the list. When I tried
  to connect to it, it asked for the wepkey which we typed again yet it fails
  to connect. It's not a weak signal, the router is maybe 25 feet away and it
  shows 5 full bars.

  Any ideas clues on what I should do from here?

Well, I don't live at home so I'm not there and can't get this info. I'm going to be visiting this weekend to mess around with it again.

All the computers are on the same work group and before they moved all the desktops were in the same room and connected directly to the router aside from the laptop of course. It just doesn't make any sense to me. The laptop connects just fine full signal strength but it just can't access websites by domain name. Then the other pc we tried connecting to the wifi just can't connect at all even though it sees the network in the list and it too has full signal strength.

For what its worth, its a Wireless G network 54mbps. I believe it is broadcasting on channel 4 although I don't remember exactly. I do remember that it was the same channel that the netgear software was trying to use when we used the wizard instead of manually setting up the connection. Also I remember it was configured to use B&G because I would sometimes come over with my laptop that had a B card.

I had this dns thing happen to me one time before on a lan and it was just one pc that was affected, and unfortunately I don't remember what I did to fix it.

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