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I have downloaded the setup file for 4.0 and when I click on it to run, it says that I need to reboot for an earlier version (which I have done several times). There is nothing to uninstall, and I can't get it to work.

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  • Last reply by cor-el

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I tried to update from 3.6 to 4.0. When the program was installing, it said I needed to reboot. I tried and nothing happened. I tried to reinstall and it said that I needed to reboot for previous version. I tried and still nothing. I have uninstalled all versions running and tried again but still does not work.

I tried to update from 3.6 to 4.0. When the program was installing, it said I needed to reboot. I tried and nothing happened. I tried to reinstall and it said that I needed to reboot for previous version. I tried and still nothing. I have uninstalled all versions running and tried again but still does not work.

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Run the Firefox program once as Administrator (right-click: Run as Administrator).

If that doesn't solve the problem then remove the Firefox program folder to do a clean reinstall.

Download a fresh Firefox copy and save the file to the desktop.

  • Uninstall your current Firefox version and remove the Firefox program folder before installing that copy of the Firefox installer.
  • Do not 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 in the Firefox Profile 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.