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Firefox keep crashing on start

  • 2 replies
  • 2 have this problem
  • 10 views
  • Last reply by zamronypj

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Cannot open firefox. it crashes as soon as it starts

Cannot open firefox. it crashes as soon as it starts

Chosen solution

You can try to see if you can start Firefox in Safe Mode:

  • On Windows, hold down the Shift key while starting Firefox with a double-click on the Firefox desktop shortcut
  • On Mac, hold down the Options key while starting Firefox
  • Help > Restart with Add-ons Disabled

Do a clean reinstall and delete the Firefox program folder before (re)installing a fresh copy of the current Firefox release.

Download a fresh Firefox copy and save the file to the desktop.

if possible uninstall your current Firefox version to cleanup the Windows registry and settings in security software.

  • Do NOT remove personal data when you uninstall your current Firefox version, because all profile folders will be removed and you lose personal data like bookmarks and passwords from profiles of other Firefox versions.

Remove the Firefox program folder before installing that newly downloaded copy of the Firefox installer.

  • (32 bit Windows) "C:\Program Files\Mozilla Firefox\"
  • (64 bit Windows) "C:\Program Files (x86)\Mozilla Firefox\"

Your bookmarks and other personal data are stored in the Firefox profile folder and won't be affected by an uninstall and (re)install, but make sure that "remove personal data" is NOT selected when you uninstall Firefox.

If you keep having problems then also create a new profile.



Do a malware check with some malware scanning programs on the Windows computer.
Please scan with all programs because each program detects different malware.
All these programs have free versions.

Make sure that you update each program to get the latest version of their databases before doing a scan.

You can also do a check for a rootkit infection with TDSSKiller.

See also:

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Chosen Solution

You can try to see if you can start Firefox in Safe Mode:

  • On Windows, hold down the Shift key while starting Firefox with a double-click on the Firefox desktop shortcut
  • On Mac, hold down the Options key while starting Firefox
  • Help > Restart with Add-ons Disabled

Do a clean reinstall and delete the Firefox program folder before (re)installing a fresh copy of the current Firefox release.

Download a fresh Firefox copy and save the file to the desktop.

if possible uninstall your current Firefox version to cleanup the Windows registry and settings in security software.

  • Do NOT remove personal data when you uninstall your current Firefox version, because all profile folders will be removed and you lose personal data like bookmarks and passwords from profiles of other Firefox versions.

Remove the Firefox program folder before installing that newly downloaded copy of the Firefox installer.

  • (32 bit Windows) "C:\Program Files\Mozilla Firefox\"
  • (64 bit Windows) "C:\Program Files (x86)\Mozilla Firefox\"

Your bookmarks and other personal data are stored in the Firefox profile folder and won't be affected by an uninstall and (re)install, but make sure that "remove personal data" is NOT selected when you uninstall Firefox.

If you keep having problems then also create a new profile.



Do a malware check with some malware scanning programs on the Windows computer.
Please scan with all programs because each program detects different malware.
All these programs have free versions.

Make sure that you update each program to get the latest version of their databases before doing a scan.

You can also do a check for a rootkit infection with TDSSKiller.

See also:

more options

I have somehow solved this problem when suddenly there was dialog showed up that tell me to start in Firefox Safe Mode. Then after that all running smoothly.