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Firefox won't load or slow every time since 18 update I have all necessary cleaning done--just don't open right now


Lately Firefox does not load on my Vista--especially since update 18 happened. It shows that Firefox is running in the task manager but the page doesn't come up. This is every time I try to start the browser. It runs once I can get it to come up--but it never ever comes up the first time without going into task manager and finding the file it is in and starting it there as "administrator". This is very very annoying--before I uninstall and change browser back to Chrome which has its own issues--perhaps you can enlighten me as to how to fix this problem--it needs a patch? Don't tell me to dump history cookies etc. This I have already tried and it doesn't do anything--the problem persists. Any solutions for me? Thanks Lr

Additional System Details

Installed Plug-ins

  • Shockwave Flash 11.5 r502
  • 0.3
  • SiteAdvisor
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in Web pages. For more information, visit the QuickTime Web site.
  • McAfee MSC FF plugin DLL
  • Next Generation Java Plug-in 1.6.0_37 for Mozilla browsers
  • NPRuntime Script Plug-in Library for Java(TM) Deploy
  • Adobe PDF Plug-In For Firefox and Netscape "9.5.2"
  • McAfee Virtual Technician plugin for Mozilla (Gecko Version: 1.8b1)
  • 5.1.10411.0
  • Picasa plugin
  • A component of your photo software powered by RocketLife
  • iTunes Detector Plug-in
  • The Hulu Desktop Plugin allows Hulu.com to integrate with the Hulu Desktop application.
  • Office Live Update v1.5
  • Provides additional functionality on Facebook. See our web site for details.
  • Google Updater pluginhttp://pack.google.com/
  • Windows Presentation Foundation (WPF) plug-in for Mozilla browsers
  • np-mswmp
  • Yahoo Application State Plugin


  • User Agent: Mozilla/5.0 (Windows NT 6.0; rv:18.0) Gecko/20100101 Firefox/18.0

More Information

Tyler Downer
  • Administrator
  • Moderator
1164 solutions 6634 answers

The Reset Firefox feature can fix many issues by restoring Firefox to its factory default state while saving your essential information. Note: This will cause you to lose any Extensions, Open websites, and some Preferences.

To Reset Firefox do the following:

  1. Go to Firefox > Help > Troubleshooting Information.
  2. Click the "Reset Firefox" button.
  3. Firefox will close and reset. After Firefox is done, it will show a window with the information that is imported. Click Finish.
  4. Firefox will open with all factory defaults applied.

Further information can be found in the Reset Firefox – easily fix most problems article.

Did this fix your problems? Please report back to us!

  • Top 10 Contributor
  • Moderator
10739 solutions 96657 answers

A possible cause is security software (firewall,anti-virus) that blocks or restricts Firefox or the plugin-container process without informing you, possibly after detecting changes (update) to the Firefox program.

Remove all rules for Firefox and the plugin-container from the permissions list in the firewall and let your firewall ask again for permission to get full unrestricted access to internet for Firefox and the plugin-container process and the updater process.


jcplay002 0 solutions 1 answers

Firefox 18 slow should not be by security software.

Because a minute ago install firefox 17 is normal , but install firefix 18 is very slow.

seanlon11 0 solutions 2 answers

I have upgraded FF 18 and having the same issue. I also went through the steps to reset the browser to factory defaults, and it is still slow.

After a few minutes, I receive the following Script Warning after visiting a popular site:

A script on this page may be busy, or it may have stopped responding. You can stop the script now, or you can continue to see if the script will complete.

Script: http://choices.truste.com/ca?pid=valueclick01&aid=valueclick01&cid=1&c=183962460_7_782955&w=160&h=600&plc=tr:12

My Specs:

  • FF 18.0.1
  • Windows 7 SP1 32-bit machine
  • 4G of RAM
  • 2.67 Ghz Intel Core

I want to remain loyal to FF, so I hope this is resolved quickly.

Modified by seanlon11

Question owner

I have tried the steps you suggested and FF is still slow upon opening. It hangs at 12,000 k apprx in the task manager and takes a minute to finally load often after opening in task manager and going to the folder in task manager and opening as administrator. Thanks for your efforts but 18 has issues with my Vista 32 bit machine. It is too slow to fully open. I do have the script trying to load message issue on facebook--I can click on that message or not--it still doesn't fix anything--it does not necessarily seem related to Firefox slowness but could have something to do with it. Other suggestions?

Mythica 0 solutions 3 answers

I have had this problem for months and I can't begin to tell you how sick i was of that "waiting for server" message and pages just not loading. I now have FF 18.0.1 installed on a Win7 64bit system. The only virus protection I know of is MS Security Essentials & spybot (it was slow before spybot) and the windows firewall. I read the instructions above, and the basis about program updates made sense so I opened up the windows firewall and did a reset. I saw a dramatic speed increase, going from 30+ seconds to load a page to a max of 5 seconds to load. OMG why didn't someone tell me about this while i still had hair left to pull out?! I hope this information helps someone else. Mythica {Under.Her_Rock}

mano1982 0 solutions 2 answers

Hi, not sure if this will help, but it worked for me. I tried everything on posts but failed. Finally noticed that when I moved the browser window to the main monitor, the speed got restored. (I use two monitors btw). You can try this if you are using two monitors.

Mythica 0 solutions 3 answers

I spoke too soon. It's back and bad as ever. I have no idea why, it's making me nuts. For just a few minutes clearing the firewall helped but I have no idea why as it doesn't persist. *sighs* Any other answer out there? I'm ready to change browsers since the others don't do this.

agyath 0 solutions 1 answers

I think, the problem is with "graphics card switching". When you are connected to a monitor, the dedicated graphics card is on and firefox uses that. Once you disconnected from the monitor, the dedicated graphics card turns-off and integrated graphics card turns-on. that when I notices this slowness. I think, it is a bug in firefox-18. Hoping the team will resolve it in 19. Firefox19 is only beta-3 so do not want to switch there yet. I have started to close-restart firefox, It helps.

mano1982 0 solutions 2 answers

Today, my friend suggested changing the refresh rate of both monitors. I increased it from 60Hz to 75Hz. Now Firefox works fine on both monitors. Hope this helps.

Modified by mano1982

Mythica 0 solutions 3 answers

I have had this problem in Firefox from Dec of 2011, so it isn't just with 18 for me. i switched to chrome and while it has some delay too, it's nothing like firefox. Come on mozilla... no one wants to sit and wait on their browser to load! It's just beyond frustrating and straight into annoying!

dbikekc01 0 solutions 1 answers

I stumbled across an apparent quick fix. We'll see if it works after I restart the machine. Restart FF with Add-on disabled (under the help menu), then close it and restart it normally. Worked for me at this point.

dmbwharfrat 0 solutions 1 answers

Helpful Reply

I have 5 different Win7 64-bit installations. As soon as i upgraded to FF18...EVERY single systems browser experience slows to a crawl. CPU and memory spike beyond control. In fact I have to use Chrome to browse. This is so incredibly unacceptable. My entire family is soooo frustrated. They have reverted to IE, and i provided each device with a fresh install of Chrome, no issues whatsoever.

As for suggestions here, I have no intention of following any of these lame instructions to check anti-virus, video card switching, or resetting FF to defaults which will cause loss of some of the personalization.

Its a bloody shame. Farewell FF. Enjoy your poorly QA'ed release....!!!

Tyler Downer
  • Administrator
  • Moderator
1164 solutions 6634 answers

If you won't do any troubleshooting then naturally we can't help you.

seanlon11 0 solutions 2 answers

I have also tried the Beta version (19 b3), and I have the exact same slowness issue (see my specs above). I'm not sure if it helps, but while trying to access drudgereport.com, after a few minutes, I receive the following error message:

A script on this page may be busy, or it may have stopped responding. You can stop the script now, or you can continue to see if the script will complete.

Script: http://choices.truste.com/ca?aid=attssl01&pid=mec01&language=en&c=_LBcLB_&cid=0112mec&sid=_LBsidLB_&js=st_2&cam=3:79

I have used FF for years now, and have no plans to permanently change. However, for the time being I have to use Chrome.

I am willing to help test FF, but I do not know the process. If someone can send me a link to the details, I would be happy to help.

- Sean

Modified by seanlon11