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Firefox not starting

  • 8 cavab
  • 2 have this problem
  • 40 views
  • Last reply by FredMcD

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Firefox exe visible in TaskMan but doesn't do anything

Profile manager and Safe mode will not start

Renaming profiles.ini and reinstalling makes no difference. Using Windows 10, Firefox has worked fine for (years)

Firefox exe visible in TaskMan but doesn't do anything Profile manager and Safe mode will not start Renaming profiles.ini and reinstalling makes no difference. Using Windows 10, Firefox has worked fine for (years)

All Replies (8)

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https://support.mozilla.org/en-US/kb/changes-toolbars-and-window-sizes-are-not-saved You may have corrupt xulstore.json or Localstore.rdf files.

Close Firefox. Open your file browser to this hidden location:

  • Mac: *~/Library/Application Support/Firefox/Profiles
  • Linux: *~/.mozilla/firefox/Profiles
  • Windows: %AppData%\Mozilla\Firefox\Profiles
  • *C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\Profiles
  • Windows XP: C:\Documents and Settings\<user>\Application Data
    \Mozilla\Firefox\Profiles\

Search for the above files. Then rename or delete them. Restart Firefox.

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Thanks for the fast response. I've renamed the xulstore.json file but can't see a localstore.rdf anywhere

Firefox still not starting from renaming the json file

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Start Firefox in Safe Mode {web link} by holding down the <Shift> (Mac=Options) key, and then starting Firefox.

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?

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shift + starting firefox - still goes in the background processes list but never gets to the visible applications list

This has only ever happened before if two copies of FF tried to start, or one had not closed properly before the other started. Very odd, as killing the background process always (previously) sorted this.

So, still won't launch to desktop. Having to endure MS Edge. Not an amazing experience.

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Is it worth simply doing a complete reinstall?

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Let’s do a full clean re-install;

Download Firefox For All languages And Systems {web link}

Save the file. Then Close Firefox.

Using your file browser, open the Programs Folder on your computer.

Windows: C:\Program Files C:\Program Files (x86) Note: Check Both Folders

Mac: Open the "Applications" folder. https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac

Linux: Check your user manual. If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it. See Install Firefox on Linux; https://support.mozilla.org/en-US/kb/install-firefox-linux

If you downloaded and installed the binary package from the Firefox download page, simply remove the folder Firefox in your home directory. http://www.mozilla.org/firefox#desktop ++++++++++++++++++++++++++++ Look for, and remove any Mozilla or Firefox program folders. Do not remove the Mozilla Thunderbird folder if there is one.

Do Not remove any profile folders.

After rebooting the computer, run a registry scanner if you have one. Then run the installer. +++++++++++++++++++++++++++ If there is a problem, start your Computer in safe mode and try again.

http://encyclopedia2.thefreedictionary.com/Linux+Safe+Mode This shows how to Start all Computers in Safe Mode; Free Online Encyclopedia

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Yes a clean reinstall did the trick. Thanks

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Hello,

I am glad to hear that your problem has been resolved. If you haven't already, please select the answer that solves the problem. This will help other users with similar problems find the solution more easily.

Thank you for contacting Mozilla Support.