Resetting local area connection adapter, Default gateway is unavailable in IE8

I am having three computers but having problem in only one of those three computers. First machine is a Windows 7 Home Premium 64 bit which is upgraded from Vista 64 bit, this is working well. Other one is a Windows 7 Ultimate 64 bit which is on dual-boot configuration with Windows XP. The Windows 7 before had Windows 7 RC-1 was installed which not at all had any troubles. Now through the store purchased version it has extra problem but this is not with the internet connectivity problem. Third one is the Windows 7 Professional 32-bit which was upgraded from Windows XP. This is the computer is only facing the problem. All of these are hard wired to a Linksys/Cisco router along with the cable connection. What I am not able to understand is why this trouble just happens on 1 out of 3 computers. The only dissimilarity that I can observe is 32-bit vs. 64-bit but I don’t think that this will matter? Please help.

There is possibility that the security firewall is creating the issue for that. My suggestion to you is to check the security firewall settings and you can try to change those settings to some different levels. See if that can solve the issue for you. I am saying this to you because this comes out to be the reason, many of the times for such issues. So try this out and see if that can help you. You can click here to get more information on this topic.

You can also try to reset WINSOCK, IPv4 TCP/IP, and IPv6 TCP/IP stack. If you want to give it a try then go for the steps below and see if that can help you.

1. First of all you have to click the Start, type cmd within the search box.
2. Now right click on the Command Prompt and choose "Run as Administrator"
3. Press Enter and this will open Command Prompt.
4. Type the commands below at the command prompt window.
   
   Quote:

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   netsh winsock reset catalog that resets WINSOCK entries to installation defaults.
   netsh int ipv4 reset reset.log that resets IPv4 TCP/IP stack to installation defaults.
   netsh int ipv6 reset reset.log resets IPv6 TCP/IP stack to installation defaults.

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5. Finally reboot your system and check for the issue again.

Above given steps are very correct but if that cannot help you then you can try to reset the router to its factory defaults. For that you have to hold down the reset button for about 15 seconds. See the steps.

1. Firstly, you have to turn off the modem, router and the computer.
2. Now, connect modem with router's WAN/Internet port.
3. join computer to any of the router's LAN/Network ports.
4. stay for the steady connection light subsequent to turning on the modem.
5. Now turn on router and wait about two minutes.
6. Reboot the system.
7. After booting the computer check if the issue is there or not.

You can try the steps below but before trying this, you should make the restore point for this so that you will be at the safer side.

1. Click the Windows Start button and type ‘Device Manager’ inside the search box.
2. Click the ‘Device Manager’ entry that becomes visible in the catalog beneath Control Panel to start it, find and enlarge the Network adapters group and right click on entry for the Atheros L1 adapter/ whichever network adaptor that you have.
3. Select to the advanced tab from the properties dialog box, choose Task Offload, and place its value to off.
4. Finally press, OK.

I wish that this will help you.