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Oops! This page appears broken. DNS Error - Server cannot be found.


I am using Firefox 3.6.9 so is my husband. When I go to many sites, I get this error message AFTER it displays the page for about 10 seconds. My husband can go to the same site and it stays up. We have checked my setting against his, cleared the cache and history repeatedly and mine still does it. I am using win7 64 bit and Firefox3.6.9. Please help me get this issue resolved or I will have to go back to using IE which I totally dislike, but I can view the same web pages and it does not go off. Thanks, JoAnna

Additional System Details

Sites Affected


Installed Plug-ins

  • npmnqmp 989898989877
  • Office Plugin for Netscape Navigator
  • np-mswmp
  • Adobe PDF Plug-In For Firefox and Netscape
  • 1.9.0042.0
  • Pando Web Installer
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in Web pages. For more information, visit the QuickTime Web site.
  • NPRuntime Script Plug-in Library for Java(TM) Deploy
  • RealPlayer(tm) LiveConnect-Enabled Plug-In
  • RealJukebox Netscape Plugin
  • Default Plug-in
  • Shockwave Flash 10.0 r45
  • Picasa plugin
  • Next Generation Java Plug-in 1.6.0_21 for Mozilla browsers
  • 4.0.50826.0
  • RealPlayer(tm) HTML5VideoShim Plug-In
  • Version 1.0.5, copyright 1996-2010 The VideoLAN Teamhttp://www.videolan.org/


  • User Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv: Gecko/20100824 Firefox/3.6.9 GTB7.1

More Information

Was at the link above.. when it did the "oops" thing and then I was here below...

Ziggy Maes 0 solutions 56 answers

Hello there,

Please try this: DNS Prefetching

Firefox attempts to speed up loading new websites by using DNS Prefetching, which can cause page load errors with some system configurations. To disable DNS Prefetching:

  1. In the Location bar, type about:config and press EnterReturn.
         * The about:config "This might void your warranty!" warning page may appear. Click I'll be careful, I promise!, to continue to the about:config page. 
  2. Right-clickHold down the Ctrl key while you click in the list of preferences, select New, and then select Boolean.
  3. In the Enter the preference name window, enter network.dns.disablePrefetch and click OK.
  4. Select true when prompted to set the value and click OK. 

Regards, Ziggy

Question owner

Hi Ziggy, Thanks for trying to help resolve this problem. I did all you said.. printed off your instructions and hubby read them to me.

network.dns.disablePrefetch;true ( user set boolean true )

Then I even went in and cleaned the prefetch ...pf files.. in Windows Explorer, cleared everything in browsing history, ran cc cleaner.. and did a shut down. Then rebooted.. I went to the page that I knew for sure this happens on for me, but not my husband. Low and behold.. I got the same error message!

Oops! This page appears broken. HTTP 404 - File not found.

This is also a string right about the other.. network.dns.disableIPv6;false is this string correct?

I am ready to try anything else that might work! Again Thanks for taking the time to try to help. JoAnna

notnutnat 0 solutions 1 answers

Helpful Reply

i experienced the same error. i noticed that when the error appears, the url on the address bar is something like "...pdfforge...facebook...". so i figured the pdfforge toolbar that I recently installed is the culprit... maybe it tries to link to facebook or somethin and facebook is blocked in our office network... I uninstalled the toolbar and rightly so, i did not experience the error again... btw, the error occured when opening links from Yahoo! Insider. After uninstallation though, i got "problem sending command ..." error when opening Yahoo! Insider links which disappeared after system restart. Hope this solves your problem or gives you an ideo on how to solve it... Good Luck

Modified by notnutnat

alfa75ts 0 solutions 1 answers

Helpful Reply

I was experiencing this problem too, just when i was at office though, i solved it by disabling the pdfforge toolbar and the widgi toolbar platform, in the mozilla additional components. Anything goes fine now . bye .

ChiroVette 0 solutions 2 answers

Okay, I have been getting this same problem intermittently for a while now and I seem to have solved it so this may help you guys. Now the odd thing is that it ONLY happened on some sites, and only when accessing some pf the pages, but it was extremely annoying. Like you guys, I would get the page first. It would come up normally and then a few seconds later, before I could even really read anything, it would go to the broken DNS page. Now I tried deleting all cookies and clearing my browser history, but that didn't help.

However, I noticed something peculiar and VERY interesting. Whenever I would get this error and could not make it go away, it would always take me to some generic search page (it may have been Yahoo, but I am not sure) and I would notice that as soon as I went to the so called broken page, the address bar of my browser would ALWAYS change to the same exact address and not the one I typed.

This page was ALWAYS the same and it had "Youtube downloader" in the address bar. Now this is a program that I downloaded to be able to download Youtube videos to my computer. So I think that there is something wrong with the program or installing it (or possibly the corresponding menu bar) to my PC created this strange, intermittent problem. So I tried this and it worked:

1. I got OFF the broken link page to remove that from my present broswing history. I just went to some random Google page.

2. I uninstalled Youtube Downloader and sent the developers a message telling them why I was uninstalling it and gave them my email address in case they have any questions.

3. Then I uninstalled the Youtube Downloader Menu Bar as well.

4. Then I deleted all browser history, just in case.

That cleared it up!

So for those of you experiencing this, I am guessing it has something to do with this program or perhaps there are a number of programs that cause this issue? So my suggestion is to go to the page that "breaks" your connection and look on the address bar to see what it says there. Then see if you have ANY programs installed on your computer (by going to Control Panel > Add/Remove Programs) and uninstall ALL instances of the program that seems to be named in the address line of the links that keep breaking. Then finally clear your browser of ALL history, stored passwords, cookies, etc.

Hope this helps! :)