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Firefox won't start. I tried resetting and then uninstalling/reinstalling. It says Firefox will start up after install, but it never does. Help!

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  • 6 have this problem
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  • Last reply by ericasaunt

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I have tried several times deleting and reinstalling the latest version of Firefox. It gives me a message that Firefox will start up when downloading/installation are done. Nothing happens. When I check Task Manager it says the program is running. I have clicked on the icon to open it, but nothing happens. Control Panel shows Firefox is definitely installed.

This happened all of a sudden. Nothing so far on the mozilla.org website has been useful. Any more ideas? Thanks.

I have tried several times deleting and reinstalling the latest version of Firefox. It gives me a message that Firefox will start up when downloading/installation are done. Nothing happens. When I check Task Manager it says the program is running. I have clicked on the icon to open it, but nothing happens. Control Panel shows Firefox is definitely installed. This happened all of a sudden. Nothing so far on the mozilla.org website has been useful. Any more ideas? Thanks.

All Replies (4)

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I also just tried to run my Firefox profile, but, again, nothing happens.

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Hello ericasaunt, if you see the message "Firefox is already running but is not responding", see: "Firefox is already running but is not responding" error message - How to fix it

you can also try to Starting the Profile Manager and Create a new profile, before doing that make sure firefox is closed in the Task Manager (see End Firefox processes)


thank you

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Hello ericasaunt, if the above is unhelpful you can go for a clean re-install, this means you remove Firefox program files and then reinstall Firefox. Please follow these steps:

Note: You might want to print these steps or view them in another browser.

  1. Download the latest Desktop version of Firefox from http://www.mozilla.org and save the setup file to your computer.
  2. After the download finishes, close all Firefox windows (click Exit from the Firefox or File menu).
  3. Delete the Firefox installation folder, which is located in one of these locations, by default:
    • Windows:
      • C:\Program Files\Mozilla Firefox
      • C:\Program Files (x86)\Mozilla Firefox
  4. Now, go ahead and reinstall Firefox:
    1. Double-click the downloaded installation file and go through the steps of the installation wizard.
    2. Once the wizard is finished, choose to directly open Firefox after clicking the Finish button.

Please report back to see if this helped you!

thanks again

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Thank you. I couldn't fix the problem. It was my husband's computer, anyway, and I suspect there were trojans on it. He paid someone to come over and fix it, so all is well now.

I appreciate your help.