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Firefox won't start - No error message, UAC loop

  • 4 replies
  • 2 have this problem
  • 8 views
  • Last reply by FredMcD

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I had a game freeze on me and the freeze was the kind that prevented me from accessing Task Manager to force end it. I executed a Sign Out from the Windows Security window since that always fixes the issue for me. Firefox was one of the programs running at the time that I forced the sign out. Upon signing back in, Firefox no longer loads. Execute the program, UAC pops up to ask if I am sure I want to run Firefox and I hit Yes. Instead of running, like it normally does, it prompts me with another UAC window. Hit yes, another UAC windows. No error messages, it just keeps throwing up new UAC prompts at me. I turn off the UAC and Firefox still doesn't open, but I can see in Task Manager that it keeps opening and closing instances of itself.

Restarted multiple times, didn't resolve the issue. Uninstalled it, no change. Uninstalled my antivirus since that was causing me some other issues, no change. Tried to run the profile manager and it goes into a UAC loop as well. Copied my profile, deleted the original, clean installed Firefox... no change.

I haven't been able to find any information at all about any similar issue anywhere, so I really don't know what else to do.

I had a game freeze on me and the freeze was the kind that prevented me from accessing Task Manager to force end it. I executed a Sign Out from the Windows Security window since that always fixes the issue for me. Firefox was one of the programs running at the time that I forced the sign out. Upon signing back in, Firefox no longer loads. Execute the program, UAC pops up to ask if I am sure I want to run Firefox and I hit Yes. Instead of running, like it normally does, it prompts me with another UAC window. Hit yes, another UAC windows. No error messages, it just keeps throwing up new UAC prompts at me. I turn off the UAC and Firefox still doesn't open, but I can see in Task Manager that it keeps opening and closing instances of itself. Restarted multiple times, didn't resolve the issue. Uninstalled it, no change. Uninstalled my antivirus since that was causing me some other issues, no change. Tried to run the profile manager and it goes into a UAC loop as well. Copied my profile, deleted the original, clean installed Firefox... no change. I haven't been able to find any information at all about any similar issue anywhere, so I really don't know what else to do.

All Replies (4)

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Chosen Solution

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After; Let’s do a full clean re-install;

Note: Firefox comes in three or more folders on all computers. They are;

Maintenance: (Programs Folder) <Windows Only> Firefox itself: (Programs Folder) And two folders in the profile of each user on the computer for each Firefox profile for that user.

If you remove the Firefox folder, the user profiles would not be affected.


Download Firefox For All languages And Systems {web link}

Save the file. Then Close Firefox.

Using your file browser, open the Programs Folder on your computer.

Windows: C:\Program Files C:\Program Files (x86) Note: Check Both Folders

Mac: Open the "Applications" folder. https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac

Linux: Check your user manual. If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it. See Install Firefox on Linux; https://support.mozilla.org/en-US/kb/install-firefox-linux

If you downloaded and installed the binary package from the Firefox download page, simply remove the folder Firefox in your home directory. http://www.mozilla.org/firefox#desktop ++++++++++++++++++++++++++++ Look for, and remove any Mozilla or Firefox program folders. Do not remove the Mozilla Thunderbird folder if there is one.

Do Not remove any profile folders.

After rebooting the computer, run a registry scanner if you have one. Then run the installer. +++++++++++++++++++++++++++ If there is a problem, start your Computer in safe mode and try again.

http://encyclopedia2.thefreedictionary.com/Linux+Safe+Mode This shows how to Start all Computers in Safe Mode; Free Online Encyclopedia

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Thank you so much. That seems to have done it.

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Hello,

I am glad to hear that your problem has been resolved. If you haven't already, please select the answer that solves the problem. This will help other users with similar problems find the solution.

Thank you for contacting Mozilla Support.