Hi,

Thanks for your submission and welcome to the Support Forum.

Did you try 'kill' the Firefox processes that you saw or not? If not, I would suggest to do so for all the Firefox processes you'll find. Once done, try launching Firefox again.

After removing/installing an app it's better to reboot your system so you're sure everything is gone. (in case of removal).

Thanks for your reply. Kind regards, Dakta

It is possible that your firewall or other security software blocks or restricts Firefox without informing you, possibly after detecting changes (update) to the Firefox application. Remove all rules for Firefox from the permissions list in the firewall and let your firewall ask again for permission to get full, unrestricted, access for Firefox and the plugin-container process and the updater process.

See:

• https://support.mozilla.org/en-US/kb/server-not-found-connection-problem
• https://support.mozilla.org/en-US/kb/Firewalls
• https://support.mozilla.org/en-US/kb/fix-problems-connecting-websites-after-updating

Try to start Firefox in Safe Mode to see if that works.

• Windows: hold down the Shift key while starting Firefox
• Mac: hold down the Options key while starting Firefox

• https://support.mozilla.org/en-US/kb/troubleshoot-firefox-issues-using-safe-mode

You can create a new profile to test if your current profile is causing the problem.

See "Creating a profile":

• https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles
• http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Profile_issues

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.

• https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile

djdakta said

Hi, Thanks for your submission and welcome to the Support Forum. Did you try 'kill' the Firefox processes that you saw or not? If not, I would suggest to do so for all the Firefox processes you'll find. Once done, try launching Firefox again. After removing/installing an app it's better to reboot your system so you're sure everything is gone. (in case of removal). Thanks for your reply. Kind regards, Dakta

Have tried that and to no avail. It seems to start to processes at the same time, and that is not letting it start What I have tried - CMD > taskkill /f /im/firefox.exe - uninstall and remove all files and restart - delete all files in appdata after uninstall

Nothing seems to work and firefox installer still remembers that it was installed on the computer, so i do not think it is doing a clean install merely restoring the data.

This is a problem with the profile folder.

• https://support.mozilla.org/en-US/kb/Firefox-already-running-not-responding

dominik.private said

djdakta said

Hi, Thanks for your submission and welcome to the Support Forum. Did you try 'kill' the Firefox processes that you saw or not? If not, I would suggest to do so for all the Firefox processes you'll find. Once done, try launching Firefox again. After removing/installing an app it's better to reboot your system so you're sure everything is gone. (in case of removal). Thanks for your reply. Kind regards, Dakta

Have tried that and to no avail. It seems to start to processes at the same time, and that is not letting it start What I have tried - CMD > taskkill /f /im/firefox.exe - uninstall and remove all files and restart - delete all files in appdata after uninstall

Nothing seems to work and firefox installer still remembers that it was installed on the computer, so i do not think it is doing a clean install merely restoring the data.

OK, I think it is fixed. Thank you everyone for your help. I performed a global search for any files containing Mozilla and deleted them one by one. then emptied trash restarted and reinstalled. Thank seemed to fix it as it is opening now without any problem.

@dominik.private I’m glad you found a solution to your problem! Have a nice day.