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FF won't release when it close

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  • 12 have this problem
  • 2 views
  • Last reply by cor-el

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I'm using FF 29.01 and Win 7 and am having a problem. When I close FF and want to open it later again about 75% of the time I'll get an error message that says:

"FireFox is already running,but is not responding. t920-982-6312 new Window you must first close the existing Firefox process, or restart your system".

I then have to open Task Manager and end the process by hand. FF will then open properly. I started having this problem before updating to V29.  I have also started in safe mode and it still does it.

Any suggestions will be appreciated. It's driving me crazy. Thanks Floyd

I'm using FF 29.01 and Win 7 and am having a problem. When I close FF and want to open it later again about 75% of the time I'll get an error message that says: "FireFox is already running,but is not responding. t920-982-6312 new Window you must first close the existing Firefox process, or restart your system". I then have to open Task Manager and end the process by hand. FF will then open properly. I started having this problem before updating to V29. I have also started in safe mode and it still does it. Any suggestions will be appreciated. It's driving me crazy. Thanks Floyd

All Replies (1)

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Are you using "Clear history when Firefox closes" to clear some personal data?


There are other things that need your attention.

Note that your System Details List shows multiple Flash plugins.

  1. Shockwave Flash 13.0 r0
  2. Shockwave Flash 11.2 r202

You can find the installation path of all plugins on the about:plugins page.

You can check the Flash player installation folder for multiple Flash player plugins and remove older version(s) of the plugin (NPSWF32) and possibly (re)install the latest Flash player.

  • (32 bit Windows) C:\Windows\System32\Macromed\Flash\
  • (64 bit Windows) C:\Windows\SysWOW64\Macromed\Flash\