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when I try to reopen Firefox, it says its already running and to restart my computer or close it down. But, it isn't open. This just started when I downloaded the newest version


I open Firefox, use it then close it. Next time I try to open it, I get a message saying its already open, but, it isnt. I have to constantly restart my computer to use Firefox. What can I do to fix this?

This happened

A few times a week

== I downloaded the newest version of Firefox

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Installed Plug-ins

  • -Default Plug-in
  • Adobe PDF Plug-In For Firefox and Netscape "9.3.2"
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in Web pages. For more information, visit the QuickTime Web site.
  • NPRuntime Script Plug-in Library for Java(TM) Deploy
  • Shockwave Flash 10.0 r32
  • Yahoo Application State Plugin version
  • Windows Presentation Foundation (WPF) plug-in for Mozilla browsers
  • Google Update
  • Next Generation Java Plug-in 1.6.0_20 for Mozilla browsers


  • User Agent: Mozilla/5.0 (Windows; U; Windows NT 5.2; en-US; rv: Gecko/20100401 Firefox/3.6.3 GTB7.0 ( .NET CLR 3.5.30729)

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See http://kb.mozillazine.org/Firefox_hangs and Firefox hangs or is not responding - How to fix (Hang at exit)