Start Firefox in Safe Mode {web link}

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

Firefox will not start in safe mode either, just goes through the same process and crashes.

If you can't get Firefox to open, you will have to do this the hard way. https://support.mozilla.org/en-US/kb/mozillacrashreporter

Open the file browser / explorer on your computer. Note: You may have to enable Show Hidden Folders / Files. Enter this in the address bar;

Windows: %APPDATA%\Mozilla\Firefox\Crash Reports\submitted Win 7/Vista: C:\Users\<username>\AppData\Roaming\Mozilla\Firefox\Crash Reports\submitted Win XP/2000: C:\Documents and Settings\<username>\Application Data\Mozilla\Firefox\Crash Reports\submitted Win 10: Press <Windows> + R on the keyboard. A Run dialog will open. In the Run dialog, type %APPDATA%\Mozilla\Firefox\Crash Reports\submitted <Enter>

Mac OS: /Users/<username>/Library/Application Support/Firefox/Crash Reports/submitted Linux: /home/<username>/.mozilla/firefox/Crash Reports/submitted

Copy the most Recent 5-7 File Names in the folder. Press the Reply button. Now go to the reply box and paste them in.

There are no crash reports in that folder but there are some under windows but they are large .dmp files that cannot be pasted here and there is no way of attaching files.

Use these links to create a new profile. Use this new profile as is. Is the problem still there?

https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing-inaccessible

http://kb.mozillazine.org/Profile_folder_-_Firefox#Navigating_to_the_profile_folder

https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles

https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

Type about:profiles<enter> in the address bar.

I already tried this and it did not work. The program starts in Task Manager then is suspended and then dies.

Let’s do a full clean re-install;

Note: Firefox comes in three or more folders on all computers. They are;

Maintenance: (Programs Folder) <Windows Only> Firefox itself: (Programs Folder) And two folders in the profile of each user on the computer for each Firefox profile for that user.

If you remove the Firefox folder, the user profiles would not be affected.

Download Firefox For All languages And Systems {web link}

Firefox ESR; Extended Support Release {web link}

Beta, Developer, Nightly versions https://www.mozilla.org/en-US/firefox/channel/desktop/

Install Older Version Of Firefox {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.

How to Start all Computers in Safe Mode; {web link} Free Online Encyclopedia

For some unknown reason Firefox has kicked back into life today!

So thanks for trying to help but none the wiser about what happened.

I had already re-installed Firefox the other day.

Very odd. This is not the first time a program came back to life, apparently on its own.

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