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After trying to upgrade from Firefox three it will not start, consistently saying reboot the PC to enable upgrade, and will not uninstall either.

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  • Last reply by cor-el

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I tried to upgrade from Firefox three to the latest issue. Now both versions appear to be installed on the PC. If I try to start Firefox I get a message saying reboot the PC to enable upgrade. Rebooting makes no difference, it just cycles round. I tried to uninstall both versions but neither of them will uninstall.

I tried to upgrade from Firefox three to the latest issue. Now both versions appear to be installed on the PC. If I try to start Firefox I get a message saying reboot the PC to enable upgrade. Rebooting makes no difference, it just cycles round. I tried to uninstall both versions but neither of them will uninstall.

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If there are problems with updating then best is to download the full version and uninstall the currently installed version and delete the Firefox program folder to remove any leftover files.

  • Uninstall your current Firefox version.
  • Do not remove personal data when you uninstall the current version or you lose your bookmarks and other data in the profile folder.
  • Remove the Firefox program folder before installing that newly downloaded copy of the Firefox installer.
  • 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.

If you have problems with deleting that folder then boot Windows in Safe mode (F8 on the boot screen).

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.