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Whenever a friend starts his laptop and starts Firefox (regularly updated to the latest version), it hangs for 8-10 minutes and the cooling fan noise increases noticeably. Also, the processor usage shows 80-90% while it hangs. This happens for the first time only. When he launches Firefox after that he does not face any issue even after hours of browsing.


OS: Windows 7, 64 bits


Processor : Intel Core i3, 2.26 GHz


  • He has habit of closing Firefox when multiple tabs are open and saves them before closing Firefox.

  • Temporary files deletion using CCLeaner and a virus scan is already done.

  • Windows 7 is genuine and regularly updated.

  • The problem occurs even when he starts Firefox 10 mins after he starts Windows. He had the same problem with Internet Explorer.

Is it because of some add on compatibility issue? Or bug in Firefox? Or too many startup processes?

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try to delete the history. –  inf Feb 16 '12 at 12:31

2 Answers 2

If starting Firefox with the command line firefox.exe -safe-mode results in proper behavior, then it is probably an Add-ons issue.

If starting Firefox in a different profile (use firefox.exe -ProfileManager to create one) results is proper behavior, it is likely a corrupt profile. You may need to create a new one, but it can be helpful to first use SQLite to try to repair and compact the files.

As always make a backup of the profile before attempting repairs.

I use this batch script to compact my files. Both the .bat and sqlite3.exe go in the profile directory along with the .sqlite files.

@FOR %%G IN (*.sqlite) DO ( sqlite3 %%G "VACUUM" )
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You mean another user account by profile? –  rohan-patel Feb 16 '12 at 10:32

Many "Firefox" problems are caused by incompatible themes, extensions, or programming errors in plugins. As a quick diagnostic, you may wish to switch to the default theme or, if the problem appeared after installing a new extension or after upgrading Firefox, use the add-ons manager (accessible from the Tools menu) to update or disable your extensions, before going through the diagnostic steps below. Starting with Firefox 3, the add-ons manager can also be used to disable plugins.

  • Exit Firefox completely and reboot the computer.

  • (If you can open Firefox and use the menus) clear the cache: "Tools -> Options -> Advanced -> Network / Cache (Firefox 2) or Network / Offline Storage (Firefox 3 and above) -> Clear Now" and clear any other private data you don't wish to save such as cookies and download history; if the problem isn't resolved, then:

  • Close Firefox (if open) using "File -> Exit" and make sure it is not running in the background (on some systems, you may need to wait
    awhile for the Firefox process to terminate). Optionally make a
    profile backup to safeguard your data and settings and then:

  • Customization and preference issues: Start Firefox in Safe Mode. The "Firefox Safe Mode" window will appear, containing some
    troubleshooting options. Check the boxes, "Reset toolbars and
    controls" (this will remove any toolbar customizations) and "Reset
    all user preferences to Firefox defaults" (this will remove any
    user-set preferences and restores the default theme). Next, press the button, "Make Changes and Restart". . Note: Instead of using Safe
    Mode, advanced users can rename the localstore.rdf and prefs.js files so that their customizations and settings can be easily restored. If the problem is not resolved, close Firefox and then,

  • Extension and theme issues (and hardware acceleration in Firefox 4 and above): Check the list of problematic extensions, to see if your problem is listed; if not, start Firefox in Safe Mode and, when the
    "Firefox Safe Mode" window appears, press the button, "Continue in
    Safe Mode". If the problem persists in Safe Mode, continue with the
    next numbered step. If the problem goes away in Safe Mode: (Firefox 4 and above) Turn off hardware acceleration ("Tools -> Options ->
    Advanced / General -> Use hardware acceleration when available")
    Update or uninstall the added theme or select the default theme in
    "Tools -> Add-ons -> Themes". Update, disable, or uninstall your
    added extensions via "Tools -> Add-ons -> Extensions" (see Extension issues below).

  • Profile issues: Create a new Firefox profile (You can later use the Firefox Profile Manager to return to your original profile). If the
    problem goes away in the new profile, you can either selectively copy your important profile data to the new profile and reinstall your
    added extensions and themes or you can try to fix the original

  • Plugin issues: You can disable your plugins to see if the issue is plugin-related. See Plugin issues below for details. In Firefox 3.0
    and above, use the Add-ons manager ("Tools -> Add-ons -> Plugins") to disable each plugin. If the problem persists:

  • Clean reinstall: Download a new Firefox installer from and then close Firefox completely, delete the Firefox installation
    directory and reinstall Firefox. If this does not help, you may need to uninstall Firefox completely before reinstalling it.

Hope this helps.

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Thanks for putting extraordinary effort to post answer in a well systematic manner.. I will try all of your suggestion..I really appreciate for your valuable time –  rohan-patel Feb 16 '12 at 10:46

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