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My Firefox wasn't working, so I thought I would simply delete it and reinstall. I couldn't get it to uninstall. I used Revo Uninstall and now can't reinstall.

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  • Last reply by FredMcD

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Each time I tried to reinstall Firefox, I got "Couldn't Load XPCOM."

Each time I tried to reinstall Firefox, I got "Couldn't Load XPCOM."

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Open the %PogramFiles% folder then delete manually the remaining folder about Mozilla Firefox. Then reinstall Firefox.

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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;
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