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I have a very specific problem.

We have a wifi router at home which supports three laptops and a desktop. For the past month or so, I've been unable to open a number of websites on our HP desktop, Dell laptop and my Macbook. These include everything connected with and several others. The page simply refuses to load. I can't access some other websites as well.

I've tried everything. We've rebooted the router, deleted all the cookies/download history, but nothing works. I've tried accessing these websites on IE, Chrome, Firefox and Safari. Strangely, when friends use their laptops on the same wifi connection, the websites open just fine.

What do I do? I'm getting desperate here.


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The third laptop works? – Daniel Beck Mar 16 '11 at 7:38

You could try adding an entry to your Windows' host file. This will explicitly tell which IP address to load when requesting a hostname, rather than requesting it through DNS, which you may be having problems with.

You may have trouble obtaining the IP address of the websites in question, as you usually do this by pinging their host name, and if you have a DNS problem, then ping won't be able to find the end destination. You could ping the hosts from your friend's machines, you could probably find an online ping service, or you could post the list of host names here, and we will return the IP addresses.

Once you have the IPs, open the file C:\Windows\System32\drivers\etc\hosts. Add one entry per line in the format: hostname

Save the file without an extension, and reboot.

Another solution may be to run a tracert command from DOS. If DNS is failing, you may be able to see at what point it fails. You could then provide the results to your ISP - they may be the cause of the DNS failure. You can save the results of the trace route by using the command:

tracert > c:\results.txt

A third solution could be that you need to flush your local DNS cache. Open CMD and run the command:

C:>ipconfig /flushdns

You can also use the command

ipconfig /displaydns 

to view the DNS resolver cache.

Also, some questions:

  • What anti-virus & firewall software do you have on each computer?
  • Do you have any browser security plugins?
share|improve this answer
Hi Steve! Thanks so much. I don't have any anti-virus program installed on the Macbook, I think, apart from whatever's built-in. The desktop has McAfee. And I don't think I have any security plugins either. Sorry to sound so illiterate, but how do I get the IP addresses? Also, I know the Macbook doesn't have its own version of DOS, so how would I run those commands? – user72259 Mar 18 '11 at 4:06

What steve said, but to answer your question: To get the IP addresses of the sites on a windows machine you'd NORMALLY do: start -> run -> type CMD and press enter... on the dos-type box, type ping www.[the website you need IP for] example: ping

But your problem may cause this step to fail. So instead you can go to this website and type e.g. into the box:

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