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Firefox can’t find the file at jar:file:///C:/Program Files/Mozilla Firefox/browser/omni.ja!/chrome/en-US/locale/branding/browserconfig.properties.

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  • 1 has this problem
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  • Last reply by cor-el

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This problem only started when I installed and then uninstalled Mapquest. FWIW, I can open more tabs with no problem.

This problem only started when I installed and then uninstalled Mapquest. FWIW, I can open more tabs with no problem.

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Multiple users have reported similar issues. Performing a clean reinstall of Firefox should fix any damaged or missing Firefox files while preserving your Firefox data.

Hope this helps.

WARNING: Do not use a third party uninstaller as part of this process. Doing so could permanently delete your Firefox profile data, including but not limited to, extensions, cache, cookies, bookmarks, personal settings and saved passwords. These cannot be easily recovered unless they have been backed up to an external device! See Back up and restore information in Firefox profiles.
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What is the current homepage setting?

Firefox supports multiple homepages separated by '|' (pipe) symbols.


See also this pref on the about:config page.

  • browser.startup.homepage

You can open the about:config page via the location/address bar. You can accept the warning and click "I accept the risk!" to continue.