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Firefox will not open. It says 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 have restarted my computer multiple times

Posted

Help please

Help please

Additional System Details

This happened

Every time Firefox opened

This started when...

Today. No new items were installed or added.

Application

  • User Agent: Mozilla/5.0 (Windows NT 5.1) AppleWebKit/535.2 (KHTML, like Gecko) Chrome/15.0.874.121 Safari/535.2

More Information

SafeBrowser 543 solutions 2390 answers

Sounds like Firefox is "hanging at exit". That problem is frequently caused by an Extension or a Plugin. Read all of the following articles.

NOTE: Establish a habit of exiting/closing Firefox with Firefox button > Exit or File > Exit to allow an orderly shutdown of Firefox and closing of all of the files that Firefox has open.


  1. Stop the Firefox process:
  2. Why Firefox may hang:
  3. Use Firefox Safe Mode to find a problem with an Extension or Plugin:


If this reply solves your problem, please click "Solved It" next to this reply when signed-in to the forum.

Sounds like Firefox is "hanging at exit". That problem is frequently caused by an Extension or a Plugin. Read all of the following articles.<br /><br /> NOTE: Establish a habit of exiting/closing Firefox with Firefox button > Exit or File > Exit to allow an orderly shutdown of Firefox and closing of all of the files that Firefox has open. #Stop the Firefox process: #*[http://kb.mozillazine.org/Kill_application Mozillazine - Kill application] #*Windows 7 users click [http://www.techrepublic.com/blog/window-on-windows/reap-the-benefits-of-windows-7s-task-manager/2576 here] #*Mac users: http://techheavy.com/2011/02/the-mac-task-manager/ #Why Firefox may hang: #*[http://support.mozilla.com/en-US/kb/Firefox+hangs Firefox hangs] (see Hang at exit) #*[http://kb.mozillazine.org/Firefox_hangs Firefox hangs (Mozillazine)] (see Hang at exit and Closing Firefox properly) #*[https://support.mozilla.com/en-US/kb/Firefox+is+already+running+but+is+not+responding Firefox is already running but is not responding] #Use Firefox Safe Mode to find a problem with an Extension or Plugin: #*Don't check anything when entering Safe Mode, just continue #*If the problem does not occur in Safe Mode it is probably an Extension or Plugin causing the problem #*See: #**[[Safe Mode]] and [http://kb.mozillazine.org/Safe_Mode Safe Mode (Mozillazine)] #**[http://support.mozilla.com/en-US/kb/Troubleshooting+extensions+and+themes Troubleshooting extensions and themes] #**[http://support.mozilla.com/en-US/kb/Troubleshooting+plugins Troubleshooting plugins] #**[http://support.mozilla.com/en-US/kb/Basic+Troubleshooting Basic Troubleshooting] '''If this reply solves your problem, please click "Solved It" next to this reply when <u>signed-in</u> to the forum.'''

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