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Cannot open Firefox at all. Icon recongnizes the mouseclick, but does nothing.

  • 4 replies
  • 1 has this problem
  • 2 views
  • Last reply by cor-el

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I have followed all answers on this from deleting task manager to deleting the parent.lock file, and I still get told to close Firefox or some other thing I cannot do without opening Firefox first!!

Cannot uninstall until I close the file, etc, etc. How do I get the thing to open? Nothing works!

I have followed all answers on this from deleting task manager to deleting the parent.lock file, and I still get told to close Firefox or some other thing I cannot do without opening Firefox first!! Cannot uninstall until I close the file, etc, etc. How do I get the thing to open? Nothing works!

All Replies (4)

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Hi, Please consider turning on send info to Mozilla before posting a question. This helps us help you. As I have no info from your system that would help see things that cause issues.

How about trying a install over top : So let's backup your Profile 1st which could be the issue but want to get your bookmarks and...out if possible. https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles Once you have saved your Profile please Reinstall with Current Release Firefox 58.0.2 with a Full Version Installer

If have issues still or need help with the Profile let us know.

Please let us know if this solved your issue or if need further assistance.

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I am unable to comply with recommendations because I can't even close Firefox. I cannot install or uninstall anything because I'm told that I need to close Firefox - which I cannot do - and to delete it from my Task Manager, which doesn't seem to take after several attempts at it.

It is locked up somewhere along the way and won't close, won't delete from Task and won't allow me to delete the parent.lock file because it keeps telling me that it won't because it's open.

My Firefox icon in my tray reacts to my mouseclick, and nothing opens. I cannot even import my favorites to another browser.

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Try rebooting the computer.


Some problems occur when your Internet security program was set to trust the previous version of Firefox, but no longer recognizes your updated version as trusted. Now how to fix the problem: To allow Firefox to connect to the Internet again;

  • Make sure your Internet security software is up-to-date (i.e. you are running the latest version).
  • Remove Firefox from your program's list of trusted or recognized programs. For detailed instructions, see

Configure firewalls so that Firefox can access the Internet. {web link}

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

See "Creating a profile":

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.