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When trying to install 4.0 receive message "Your Computer must be restarted to complete a previous upgrade of Firefox" and rebooting does not fix.

  • 2 replies
  • 21 have this problem
  • 1 view
  • Last reply by cor-el

cshotton
cshotton
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I've rebooted and the install for 4.0 will not continue. I keep getting the same "previous upgrade" message

I've rebooted and the install for 4.0 will not continue. I keep getting the same "previous upgrade" message

All Replies (2)

Sabrips
Sabrips
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I had this problem and it was a nightmare trying to upgrade FF. Looking here on the FF help forums I found this and it actually helped:

1. Go to: "C:\Program Files\Mozilla Firefox" 2. Deleted all files that end with "upgrade" and/or "delete" on the name.

Now you should be able to Uninstall FF and install any version that you want.

Hope it helps.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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The solution is usually to perform a clear reinstall.

See also:

Do a clean (re-)install:

  • Uninstall your current Firefox version and remove the Firefox program folder before installing that copy of the Firefox installer.
  • Don't remove personal data if you uninstall the current version.
  • It is important to delete the Firefox program folder to remove all the files and make sure that there are no problems with files that were leftover after uninstalling.

Your bookmarks and other profile data are stored elsewhere (not in the Firefox program folder) and won't be affected by a reinstall, but make sure that you do not select to remove personal data if you uninstall Firefox.