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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.

  • 2 replies
  • 192 have this problem
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  • Paskiausią atsakymą parašė Moses

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I attempt to open firefox and despite firefox NOT being open I get the following message "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."

Once restarted it works fine but does re-occure

I attempt to open firefox and despite firefox NOT being open I get the following message "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." Once restarted it works fine but does re-occure

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Press CTRL+ALT+DEL, open the task manager and click on "Processes". If Firefox is still running you can close it from there. Not a complete fix but it spares you the reboot.

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Hi,

This is a currently reported bug and it's being worked on. Mozilla will release an update to 29 tomorrow to fix some of the most commonly reported issues in the forum. You can either wait for the update or you can try the workarounds.


One workaround is to set network.seer.enabled to false

  • Navigate to about:config in your Address Bar
  • Press the "I'll be careful, I promise!" button to proceed
  • search for network.seer.enabled
  • Set that to false by right clicking and selecting Toggle