Reset Firefox Completely and Start Over from Scratch

If you’ve customized many settings in Mozilla Firefox and want to revert back to the defaults without losing your bookmarks and cookies, you can use the Refresh option.

Refresh Firefox

Start Firefox, type about:support in the address bar and press ENTER.

Click “Refresh Firefox”.

refresh firefox

It tells you that refreshing Firefox will remove your add-ons, customizations and restores default browser preferences. Click “Refresh Firefox”, and click Finish in the next dialog.

refresh firefox
reset firefox
reset firefox

What does the refresh feature do?

All of your Firefox settings and personal information are stored in a profile folder. The refresh feature works by creating a new profile folder for you while saving your important data.

Add-ons which are normally stored inside the Firefox profile folder, such as extensions and themes, will be removed. Add-ons stored in other locations, such as plugins, will not be removed but any modified preferences (such as plugins you have disabled) will be reset.

Firefox will save these items:

  • Bookmarks
  • Browsing and download history
  • Passwords
  • Open windows and tabs
  • Cookies
  • Web form auto-fill information
  • Personal dictionary

These items and settings will be removed:

  • Extensions and themes
  • Website permissions
  • Modified preferences
  • Added search engines
  • DOM storage
  • Security certificate and device settings
  • Download actions
  • Plugin settings
  • Toolbar customizations
  • User styles
  • Social features.

Source: Mozilla Firefox KB

Completely Reset Firefox to defaults

If refreshing Firefox doesn’t fix a problem you’re facing, you may want to start over completely. Here is how to completely reset Firefox (for all browser profiles).

Important: The following procedure resets all Firefox settings to default, for all browser profiles. It deletes your browser profiles, bookmarks, extensions, themes, cache, browsing history, passwords, cookies, and web form auto-fill information.

You may want to export your bookmarks and cookies or sync them online before proceeding further.



Close all instances of Firefox

Open this folder: %AppData%\Mozilla by typing it in Explorer address bar.

Rename “Extensions” to “Extensions-old” and “Profiles” to “Profiles-old”

completely reset firefox

Then open: %LocalAppData%\Mozilla\Firefox

Rename “Profiles” to “Profiles-old”

completely reset firefox

That’s it! Start Firefox now. The “first run” screen will appear.

refresh firefox completely

If you have a Firefox account and had synced your bookmarks, passwords, tabs, etc. you should be able to login to the account and get (sync) your stuff back. It’s however prudent to have local copies of your bookmarks, passwords, etc. before resetting Firefox.


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About the author

Ramesh Srinivasan founded Winhelponline.com back in 2005. He is passionate about Microsoft technologies and he has been a Microsoft Most Valuable Professional (MVP) for 10 consecutive years from 2003 to 2012.

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