Tricky internet connection problem

Hi and thanks in advance for your help:

I have a cable modem connected to a Belkin wireless router. My desktop (Intel I7, 6 gb ram, plenty of hd, 3x sli nvidia 250 win7) is connected to it via LAN, as is the TV and printer (printer is also wireless). I also have a laptop (using to make this post), smart phone (Droid RAZR MAXX) and PSPGO. All connect to the internet just fine, and show up in the Network via Computer folder. Running Windows 7 on both the desktop and the laptop, both legit copies. Norton Antivirus on both. I can transfer files between shared folders on the desktop and laptop. The printer/scanner is connected to the router, and printing from the desktop is not a problem.

HOWEVER> I cannot access the internet on the desktop. The Network and Sharing Center says that there is no connection to the Internet. Troubleshooting doesn't do any good, and I can't seem to find anything in the settings. IE or Chrome, neither connect to the internet; same for any sort of update check by Norton or whatever.

But its not like the connection isn't there: I'm logged onto the internet without any problem via the laptop, and my smart phone has no problem using the wifi to connect as well.

I'm stymied. Please help, I'll download/print whatever you need.

 

Just a thought... On the desktop PC, if you do an "IPCONFIG" from the command prompt, is the default gateway the IP address of your router?

 

Yes it is.

 

Is that good or bad?

 

The default gateway is where your computer hands traffic that is destined for an IP address that is not on your local network. On a home network, it is typically the IP address of your home router. To confirm, you could check to see what IP address one of your functioning computers is using for the gateway. Can you ping that IP from the desktop? If you perform a trace route (TRACERT) to an internet destination that accepts ICMP traffic (such as Google), do you see a hop to/through your router's IP address? Some commands that may be helpful to you in troubleshooting...

ping /?
tracert /?
ipconfig /all

My next thought would be, what DNS servers are the functioning computers using and are they the same on the desktop? An "IPCONFIG /ALL" would display that information. Look for the "DNS Servers" section.

 

Also, is the desktop configured to use DHCP or did someone enter an IP address manually at some point in time? If it was on another network using a static IP, and then moved to yours, that could also be a problem. You might want to make sure you're obtaining an IP via DHCP on your desktop. Finally, if your desktop has an IP address that starts with "169.254.*.*", you probably aren't obtaining an IP address from your router. Is the desktop wireless or is there a patch cable from the PC right to the router?

 

When I run ipconfig on the desktop it lists two rows of numbers for the default gateway, the first of which is all zeros, the second is the same default gateway that is shown on the desktop.

I tried pinging the ipv4 address as well as the default gateway from both the laptop and the desktop. Pinging the default gateway from the desktop gets 0ms, but all other pings had more than zero.

How do I " make sure [I'm] obtaining an IP via DHCP on [my] desktop"?

The desktop is connected via LAN cable, the laptop via wifi, both to the router.

 

If I run ipconfig /all on this laptop, the dns server, default gateway, and dhcp server are all the same as the address of the router. Same with the desktop, except, like I said in the previous post, it gives two sets of numbers for the default gateway 0.0.0.0 and xxx.xxx.x.x
I can not run a trace route from the desktop, but can from the laptop.

Would creating a new internet connection on the desktop do anything?

I am not all that familiar with networking settings (dhcp/ip/etc), and feel out of my element, so if anyone would be willing to give more detailed/dumbed down help, that would be nice

 

I think we fixed it, so far so good, we'll see if it sticks after the windows updates finish installing.

Thanks for your help!