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After most recent update, Firefox keep hanging intermittently with "Not Responding".


After the most recent update, my Firefox browser begins to hang intermittently with "Not Responding". I have checked the extensions and plug-in like Java, all of them are the latest updated ones. Everytime I open a new site or click on links to load another page, it happens. Every single time.

Additional System Details

Installed Plug-ins

  • -3D Life Player( For more information, visit the 3D Life Player web site.
  • Office Plugin for Netscape Navigator
  • np-mswmp
  • npdivxplayerplugin
  • Adobe PDF Plug-In For Firefox and Netscape
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in Web pages. For more information, visit the QuickTime Web site.
  • 1.9.0009.1
  • DivX Web Player version
  • NPRuntime Script Plug-in Library for Java(TM) Deploy
  • Default Plug-in
  • Provides additional functionality on Facebook. See our web site for details.
  • Shockwave Flash 10.1 r53
  • Adobe Shockwave for Director Netscape plug-in, version 11.5
  • GEPlugin
  • Yahoo Application State Plugin version
  • 4.0.50524.0
  • Office Live Update v1.5
  • Windows Presentation Foundation (WPF) plug-in for Mozilla browsers
  • Google Updater pluginhttp://pack.google.com/
  • Google Update
  • Next Generation Java Plug-in 1.6.0_20 for Mozilla browsers


  • User Agent: Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv: Gecko/20100625 Firefox/3.6.6 (.NET CLR 3.5.30729)

More Information

Question owner

I updated my firefox to this same version and this problem came along. I work on Windows 7 but i think the problem is with the browser not with the OS. I didnt added any new addons but this problem is very frequent.

Question owner

Same problem very annoying. I thought it was some flash pages at first but then it starts to hang randomly.

Question owner

I have the same problem. I am using Mac OS X 10.5.8. Firefox just updated itself and hangs when I try to quit the app. I deleted the .plist file and it continues to hang when the app quits.

Question owner

The same problem here but i cant use it, every single click makes firefox unable to responde, any solution?

Question owner

I deleted the old copy and installed a fresh copy. The problem still exists. So, is Mozilla going to do anything about it? Or just "this is open source" so get help from somebody else?

Question owner

Me Too ..... But I upgraded to 3.6 to, I thought, fix the "this program is not responding" box. Instead I find same problem, just different Firefox version.

This has been an ongoing battle for SEVERAL WEEKS now -

I agree that it is completely random .... however the longer this continues, the more likely the "not responding" box will show up after second or third "click" ie open program, select option, click go ..... page fades & box appears .... "not responding" etc..What follows is absolutely nothing else will respond either .......

Early on was hounded by Adobe Update whether I wanted it or not ... this has stopped, but hanging problem still stronger then ever.

Need some guidance here please .......

Question owner

Same problem with 3.6.6 on the Macintosh platform. Hangs for a while on loading and when moving from one site to another.

Question owner

Same problem after updated to 3.6.6 when I open the flash

Question owner

I use firefox 3.6.6 in my laptop with windows 7 32bit and no problems at all, its a little slow on youtube, but the rest runs like always but my desktop is using windows 7 64bit and i cant use it at all, is just too slow even when i start it, it take about 20 seconds to lunch and its always "not responding", its a problem with the OS version or something?

Question owner

Me too, every few minutes Firefox will hang for a few seconds since I updated to 3.6.6. Windows 7 64bit.

My colleague sitting next to me is having the same problem since upgrading to FF 3.6.6. He's on XP SP3 32bit.

Question owner

Using Firefox 3.6.6.

Nothing happens when clicking "Google search" button, no matter how many times. By clicking "I'm feeling lucky", then click go back one page on browser. From then on "Google search" will work.

Have to do this if going to Google home page using url, so it's not a permanent solution.

Question owner

Same problem here. Getting really frustrated with it. Don't expect any help with it, I posted on here about FF freezing unless you move your mouse over a year ago and despite dozens of people having the same problem not a peep out of Mozilla:-(

Such a great browser ruined by stupid probs.

Question owner

Same problem with Windows XP. Didn't have the problem before update :( Really annoying!!!

Question owner

same here .......... pain in the butt

Question owner

Firefox 3.6.6 is too lag, "not responding" all the time since the update of 3.6.6. I am using CometBird 3.5.3 instead.

When will the problem being resolved?

Question owner

is there a solution (temporary OR permanent) for this problem yet?

i tried EVERY possible alternative; even when opened in 'safe mode' or when installed for the first time w| NO addons or ANYthing else but the original default settings, still does the same thing.

mozilla people?? really?? no answer|feedback|suggestions, anything at all from u guys??

if it isnt a version (browser, OS, addons, etc) issue, what is it that separates us from the users not having the problem?

this is is very frustrating; h|e it's even more frustrating when there is no response from tech support. is it because there havent been enough people who have reported this same issue so there can be some interest & find a fix; OR is it that u dont know; OR that there is not & will not be any fix?

we cant continue being users if we cannot use it. it's really my favorite browser, but if it doesn't work & u guys dont have a fix for it, then users w| this same problem wont have any other option but to switch to a different browser permanently.

really mozilla??? nothing? a reply would be very nice...

Question owner

There is an update 3.6.7 just being released.

I am using it, but the "not responding" problem still persisted! Firefox's performance is not up to expected as before!

What's wrong?

Question owner

I also have the not responding issues. It happens on at different time intervals and multiple page types. It froze on yahoo, google, news sites, and so many others. The browser worked perfectly until my windows xp system was automatically updated to the latest browser.

Can I go back easily to an older browser?

Question owner

FireFox 3.6.6, but I think from 3.6.2 on it went wrong.

I have a dualcore Laptop and a desktop on Windows 7 x64, one desktop (Pantium 4) on XP x64. None of these are capable of running Firefox without it running full-cpu for minutes at a time. Every file download makes it hang, sometimes randomly. Twitter messages take 1-2 second per entered letter.

This morning I found my laptop to be extremely hot, turns out Firefox's been hammering my CPU all damn night for no reason. Something about a script not responding, but it still keeps hammering my CPU rather than pausing it.

It takes minutes to start and hogs up more and more memory.

This has been going on for a long time and NO ONE I know doesn't have this problem.

I'm switching to Chrome. Thanks Mozilla for your previously awesome browser and starting the browserwars, but you have totally screwed up now. Goodbye.

Question owner

Happening to me too Windows 7 64 bit desktop but rarely happens on laptop Windows XP 32 bit so I think its time for me to switch to chrome. There have also been good reports coming through for IE 9 - but dont hold your breath. Even though it has good support for CSS3 and HTML 5, chances are, plugins and background tasks etc will slow this browser down.

These days people want browser speed to match the speed they are getting on broadband web app use and a browser that hangs or doesnt repond and quite frankly this has been happening to me since FF 3.5 and I am on 3.6.6 now so Mozilla hasnt really addressed the issue yet!