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when I close window and try to reopen I can't message says already running but not responding and only fix is to restart computer. How can I fix this?

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If I close the window either by x'ing out or using control + w, the window will close but if I try to reopen it, I get a pop up that says Firfox cannot open because it is already running but is not responding. Please close the window (?????) or restart the computer. The only way to get back on is to restart. This is very frustrating!

If I close the window either by x'ing out or using control + w, the window will close but if I try to reopen it, I get a pop up that says Firfox cannot open because it is already running but is not responding. Please close the window (?????) or restart the computer. The only way to get back on is to restart. This is very frustrating!

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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.



Not related to your question, but...

You may need to update some plug-ins. Check your plug-ins and update as necessary: