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Firefox XPCOM error after Firefox Auto Update on Win 7 32bit

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  • 1 has this problem
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  • Last reply by FredMcD

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Error msg "Couldn't load XPCOM" after Firefox updated itself on pc running Win 7 SP1. Firefox won't load. No updates to Win 7 were made recently.

Error msg "Couldn't load XPCOM" after Firefox updated itself on pc running Win 7 SP1. Firefox won't load. No updates to Win 7 were made recently.

All Replies (4)

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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) 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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An error message about XPCOM missing or about platform version usually happens because of a failed Firefox update that left you with a mixture of old and updated files in the Firefox program folder. This can happen in case security software was keeping a handle of some of the files in the Firefox program folder preventing Firefox from replacing all the files. You need to do a clean reinstall like posted above and remove the Firefox program folder to ensure that all files are replaced. You may have to disable security software temporarily in case the problem persists.

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Instead of following your advice in detail, I simply reinstalled Firefox from the link you provided. After installation, the error was gone. No other changes made to Win 7 or security settings.

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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 more easily.

Thank you for contacting Mozilla Support.