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Unable to Install Firefox 5, Firefox 4 won't boot. FF5 says I must close 4 before installing but 4 is not open. I am in a loop. So now I can't use any Firefox What to do?


I got a message under my original Firefox telling me to update. I followed instructions and downloaded new files for Firefox 5. Download was successful. When I followed Wizard to set up, I am told to close Firefox 4 which stopped working. When I click on old icon nothing happens so I am stuck using Internet explorer which I hate. I have tried multiple times to install 5 and always end up in the close old version of firefox before you install 5 loop. Running Windows 7 Home edition

Additional System Details

This happened

Not sure how often

This started when...

after I downloaded firefox 5 files

Installed Plug-ins

  • Gecko default plugin
  • Runs Java applets using the latest installed versions of Java. For more information: Java Embedding Plugin. Run version test: Java Information.
  • npmnqmp 071503000004
  • Version
  • Google Talk Plugin Video Accelerator version:
  • Shockwave Flash 10.1 r102
  • Java Plug-In 2 for NPAPI Browsers
  • The QuickTime Plugin allows you to view a wide variety of multimedia content in web pages. For more information, visit the QuickTime Web site.
  • LogMeIn remote control components
  • Gears for Safari
  • iPhoto6


  • User Agent: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; en-US; rv: Gecko/20100202 Firefox/3.5.8

More Information

Nothing words. When I click on icon for four, the loop goes round and round and round and never opens.
Five won't install until 4 is closed but it's not open.

kurtking 0 solutions 1 answers

My situation is a similar 4 - 5.0.1 upgrade in my laptop XP home SP3. But the day started out with my FF link not working because the program (and most of its components) had vanished from Program Files\Mozilla Firefox. Maybe as a by-product of the previous session having ended with a forced low-battery shutdown? Then I installed FF4.0 (that was the latest setup I had, although I thought I had been on 5) and it immediately advised the upgrade. (My tabs and add-ons appeared normal.) When the upgrade finished it required a reboot to finish the upgrade. And that began the loop of requiring the reboot to finish the prior upgrade.

I tried removing FF with XP's Add/Remove Programs but that also prompts for the pending reboot instead of starting the removal.

Question owner

I hated IE so I tried Chrome and love it. I don't have the time to troubleshoot FF5.