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Couldn’t load XPCOM

  • 1 reply
  • 1 has this problem
  • 19 views
  • Last reply by FredMcD

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Hola, tengo un problema, Firefox ha dejado de cargar, da este mensaje "Couldn’t load XPCOM" he intentado hacer otro perfil, he borrado las carpetas he reinstalado... pero sigue dando el error. gracias.

Solucionado viendo un video en Youtube:, por alguna extraña razón, simplemente cambiando el nombre de Firefox.exe por firefox1.exe, carga y funciona a la perfección

Hello, I have a problem, Firefox has stopped loading, it gives this message "Couldn't load XPCOM" I have tried to make another profile, I have deleted the folders I have reinstalled... but it continues to give the error. Thank you.

Hola, tengo un problema, Firefox ha dejado de cargar, da este mensaje "Couldn’t load XPCOM" he intentado hacer otro perfil, he borrado las carpetas he reinstalado... pero sigue dando el error. gracias. Solucionado viendo un video en Youtube:, por alguna extraña razón, simplemente cambiando el nombre de Firefox.exe por firefox1.exe, carga y funciona a la perfección Hello, I have a problem, Firefox has stopped loading, it gives this message "Couldn't load XPCOM" I have tried to make another profile, I have deleted the folders I have reinstalled... but it continues to give the error. Thank you.

Modified by miguelirigoras

All Replies (1)

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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 program folder, the user profiles would not be affected.


Download Firefox For All languages And Systems {web link}

Firefox ESR; Extended Support Release {web link}

Beta, Developer, Nightly versions https://www.mozilla.org/en-US/firefox/channel/desktop/

Install Older Version Of Firefox {web link} Be sure to read everything here.


Download and save the program you want. 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.

How to Start all Computers in Safe Mode; {web link} Free Online Encyclopedia