Recent answers to [Tip / Information] When you download an upgrade does the original slow down?https://support.mozilla.org/en-US/questions/10955752015-11-23T05:32:53-08:00If there are problems with updating or with the permissions then best is to download the full versio2015-11-23T05:32:53-08:00cor-elhttps://support.mozilla.org/en-US/questions/1095575#answer-809821<p>If there are problems with updating or with the permissions then best is to download the full version and trash the currently installed version to do a clean install of the new version.
</p><p>Download a new copy of the Firefox application and save the disk image file to the desktop
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<ul><li>Firefox 42.0: <a href="https://www.mozilla.org/en-US/firefox/all/" rel="nofollow">https://www.mozilla.org/en-US/firefox/all/</a>
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<ul><li>Trash the current Firefox application (open the Applications folder in the Finder and drag the Firefox application to the Trash) to do a clean (re)install
</li><li>Install the new version that you have downloaded
</li><li><a href="https://support.mozilla.org/kb/Installing+Firefox+on+Mac" rel="nofollow">https://support.mozilla.org/kb/Installing+Firefox+on+Mac</a>
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<p>Your personal data like bookmarks is stored in the Firefox profile folder, so you won't lose personal data when you uninstall and (re)install or update Firefox, but make sure NOT to remove personal data when you uninstall Firefox as that will remove all Firefox profile folders and you lose your personal data.
</p>I think what you can do is remove both, then do a full install.
Download Firefox For All languages2015-11-22T22:48:29-08:00fredmcd-hotmailhttps://support.mozilla.org/en-US/questions/1095575#answer-809693<p>I think what you can do is remove both, then do a full install.
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<p><strong><a href="http://www.mozilla.org/en-US/firefox/all/" rel="nofollow">Download Firefox For All languages And Systems</a></strong> {web link}
Save the file. Then;
</p><p>Using your file browser, open the <strong>Programs Folder</strong> on your computer.
</p><p><strong>Windows:</strong> C:\Program Files
C:\Program Files (x86)
<strong>Mac:</strong> Open the "Applications" folder.
<strong>Linux:</strong> Check your user manual.
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Look for, and rename any Mozilla or Firefox folders by adding <strong>.old</strong> to them.
</p><p>After rebooting the computer, run a registry scanner. Then run the installer.
If all goes well, remove the OLD folders when you are done.
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