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Firefox does not open; if it does, it crashes after some time.

  • 2 replies
  • 1 has this problem
  • 16 views
  • Last reply by FredMcD

Pratyush
Pratyush
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The issue started a week ago. I have the latest update of Firefox. I am using Windows 10, with satisfactory system specifications to run Firefox. I use Quick Heal Total Security. I have been using Firefox without issues since two years now. I do not use any extensions or add-ons. When I start Firefox, the following message pops up- "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window", and there are two options to either 'close firefox' or 'cancel'. I have already tried uninstalling Firefox and reinstalling multiple times. The issue comes up after a few launches. Sometimes, when I restart laptop, it might open and work fine. But when I close and re-launch Firefox, the issue pops up again.

Please help me solve the problem.

The issue started a week ago. I have the latest update of Firefox. I am using Windows 10, with satisfactory system specifications to run Firefox. I use Quick Heal Total Security. I have been using Firefox without issues since two years now. I do not use any extensions or add-ons. When I start Firefox, the following message pops up- "Firefox is already running, but is not responding. The old Firefox process must be closed to open a new window", and there are two options to either 'close firefox' or 'cancel'. I have already tried uninstalling Firefox and reinstalling multiple times. The issue comes up after a few launches. Sometimes, when I restart laptop, it might open and work fine. But when I close and re-launch Firefox, the issue pops up again. Please help me solve the problem.

All Replies (2)

FredMcD
FredMcD
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https://support.mozilla.org/kb/Firefox+is+already+running+but+is+not+responding

https://www.basezap.com/cant-open-firefox-because-a-copy-of-firefox-is-already-open-mac/

https://apple.stackexchange.com/questions/196771/cant-open-firefox-because-a-copy-of-firefox-is-already-open

http://kb.mozillazine.org/Firefox.exe_always_open

FredMcD
FredMcD
more options

In the address bar, type about:crashes<enter>. Note: If any reports do not have BP- in front of the numbers/letters, click it to submit them.

The crash report is several pages of data. We need the report numbers to see the whole report.

Using your mouse, mark the most recent 7 - 10 Submitted crash reports, and copy them. Now go to the reply box and paste them in.

Please, Do not post a screenshot ! !

aboutcrashesFx57

For more help on crash reports, see; https://support.mozilla.org/en-US/kb/firefox-crashes-asking-support +++++++++++++++++++++++++++ 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.