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Vista's System Restore stops Firefox from working, Couldn't load XPCOM, Cannot uninstall Firefox

  • 3 vastausta
  • 15 henkilöllä on sama ongelma
  • 12 näyttöä
  • Viimeisin kirjoittaja FredMcD

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Windows Vista...

After doing a System Restore, launching Firefox results in the error message "Couldn't load XPCOM", Firefox doesn't appear.

I attempted to follow the instructions in...

https://support.mozilla.org/en-US/kb/uninstall-firefox-from-your-computer

...without success.

In detail... Attempting to Uninstall via the Control Panel - nothing happens. Attempting to run the uninstall wizard manually "C:\Program Files\Mozilla Firefox\uninstall\helper.exe" - nothing happens.

What is the best way to completely remove all traces of Firefox in order to do a clean install ?

Can I download the uninstaller for Firefox, since mine doesn't work?

As long as I can remove all traces of Firefox I will be able to do a fresh install using... https://support.mozilla.org/en-US/kb/get-latest-version-firefox-windows-xp-vista


Thank you.

Windows Vista... After doing a System Restore, launching Firefox results in the error message "Couldn't load XPCOM", Firefox doesn't appear. I attempted to follow the instructions in... https://support.mozilla.org/en-US/kb/uninstall-firefox-from-your-computer ...without success. In detail... Attempting to Uninstall via the Control Panel - nothing happens. Attempting to run the uninstall wizard manually "C:\Program Files\Mozilla Firefox\uninstall\helper.exe" - nothing happens. What is the best way to completely remove all traces of Firefox in order to do a clean install ? Can I download the uninstaller for Firefox, since mine doesn't work? As long as I can remove all traces of Firefox I will be able to do a fresh install using... https://support.mozilla.org/en-US/kb/get-latest-version-firefox-windows-xp-vista Thank you.

Valittu ratkaisu

Let’s do a full clean re-install; 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) Mac: Open the "Applications" folder.
https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac Linux: Check your user manual.

Do Not remove the profiles folder.

Look for, and rename any Mozilla or Firefox program folders by adding .old to them. Do not rename the Mozilla Thunderbird folder.

After rebooting the computer, run a registry scanner. Then run the installer. If all goes well, remove the OLD folders when you are done.


If there is a problem, start your Computer in safe mode and try again.

Starting The Computer In Safe Mode;
Free Online Encyclopedia

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Valittu ratkaisu

Let’s do a full clean re-install; 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) Mac: Open the "Applications" folder.
https://support.mozilla.org/en-US/kb/how-download-and-install-firefox-mac Linux: Check your user manual.

Do Not remove the profiles folder.

Look for, and rename any Mozilla or Firefox program folders by adding .old to them. Do not rename the Mozilla Thunderbird folder.

After rebooting the computer, run a registry scanner. Then run the installer. If all goes well, remove the OLD folders when you are done.


If there is a problem, start your Computer in safe mode and try again.

Starting The Computer In Safe Mode;
Free Online Encyclopedia

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Thank you for your reply.

I have followed your instructions with the exception of fixing the registry (I am an inexperienced computer user and don't feel confident to fix the Registry)

Firefox is now up and running.

I had a slight problem with the updating process which I'll describe as it may help other people in the same situation...

As I have VISTA I had first to install version 43.0.1 and then I tried to update it via "Help/About firefox". This got me to 47.0.1 (June). I rebooted my PC and tried again. The result was still 47.0.1, I tried again, and then it updated to 48.0.2 - the latest version. So, it took a few attempts to update to the latest version.

Because I did a System Restore and this caused Firefox's uninstall routine to fail, I was wondering if the developers would consider creating a "removal tool" for messy situations, similar to what Norton provide for their products. Perhaps this could automatically clean out the Registry ?

Thank you for your help, Firefox is up and running.

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Firefox can be uninstalled just like any other program. Sometimes, however, something goes wrong, and so the above.