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When are you going to fix fox is already running, but is not responding. To open a new window, you must first close the existing Firefox process, or restart your system.

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  • Last reply by TXGuy

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When are you going to fix "firefox is already running, but is not responding. To open a new window, you must first close the existing Firefox process, or restart your system." I keep getting this and have to go to processes to stop the process. Basically the process does not stop when I exit firefox

When are you going to fix "firefox is already running, but is not responding. To open a new window, you must first close the existing Firefox process, or restart your system." I keep getting this and have to go to processes to stop the process. Basically the process does not stop when I exit firefox

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Hanging at exit is frequently caused by an Extension or a Plugin.

Kill Application In Task Manager, does firefox.exe show in the Processes tab? See: Kill Application

Causes and solutions for Firefox hanging at exit: Firefox hangs or is not responding - How to fix Firefox hangs at exit "Firefox is already running but is not responding" error - How to fix

Safe Mode You may need to use Diagnose Firefox issues using Troubleshoot Mode (click on "Safe Mode" and read) to localize the problem. Firefox Safe Mode is a diagnostic mode that disables Extensions and some other features of Firefox. If you are using a theme, switch to the DEFAULT theme: Tools > Add-ons > Themes before starting Safe Mode. When entering Safe Mode, do not check any items on the entry window, just click "Continue in Safe Mode". Test to see if the problem you are experiencing is corrected.

See: Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems Troubleshoot and diagnose Firefox problems

If the problem does not occur in Safe-mode then disable all of your Extensions and Plug-ins and then try to find which is causing it by enabling one at a time until the problem reappears. You MUST close and restart Firefox after EACH change via File > Restart Firefox (on Mac: Firefox > Quit). You can use "Disable all add-ons" on the Safe mode start window.


Other Issues: ~~red:You have installed plug-ins with known security issues. You should update them immediately.~~

You ~~red:MAY~~ need to Update Adobe Reader for Firefox (aka Adobe PDF Plug-In For Firefox): your ver. N/A; current ver. 9.3.3 (important security update release 06-29-2010; see: http://www.adobe.com/support/security/bulletins/apsb10-15.html) ~~red:Check your version here~~: http://www.mozilla.com/en-US/plugincheck/ See: http://support.mozilla.com/en-US/kb/Using+the+Adobe+Reader+plugin+with+Firefox#Installing_and_updating_Adobe_Reader You may be able to update from the Adobe Reader installed on your system instead of going to the Adobe site and downloading. Open the Adobe Reader installed on your system (in Windows, Start > Program Files, find and click Adobe Reader to open), click Help, click Check for Updates. Allow the download/update to occur. If you use this method, no need to proceed with the instructions below, but do look at the two bulleted items at the bottom "NOTE for IE:" and "Also see:". Restart Firefox and check your new version here: http://www.mozilla.com/en-US/plugincheck/ If you go to the Adobe site to download the current Adobe Reader: -use Firefox to download and SAVE to your hard drive (save to Desktop for easy access) ~~red:-See the images at the bottom left of this post to see the steps to take on the Adobe site~~ -exit Firefox (File > Exit) -In Windows: check to see that Firefox is completely closed (Ctrl+Alt+Del, choose Task Manager, click Processes tab, if "firefox.exe" is on the list, right-click "firefox.exe" and choose End process, close the Task Manager window) -In Windows: double-click on the Adobe Reader installer you just downloaded to install/update Adobe Reader

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using -P (profile_name) -no-remote does not fix this either, as it is supposed to; further, running with administrator privileges does help either [or a combo of either].

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Mark:

Did you try anything in the article above, "Firefox hangs at exit"? Did you try "Safe Mode" and the related articles "Troubleshooting extensions and themes", "Troubleshooting plugins", and "Basic Troubleshooting"?

Hanging at exit is frequently caused by an Extension or a Plugin. Finding the cause can be a tedious process, but most users who follow all of the steps, not just one or two steps, usually post back with which of their Extensions or Plugins was causing the hanging at exit.