The Reset Firefox feature can fix many issues by restoring Firefox to its factory default state while saving your essential information. Note: This will cause you to lose any Extensions, Open websites, and some Preferences.

To Reset Firefox do the following:

1. Go to Firefox > Help > Troubleshooting Information.
2. Click the "Reset Firefox" button.
3. Firefox will close and reset. After Firefox is done, it will show a window with the information that is imported. Click Finish.
4. Firefox will open with all factory defaults applied.

Further information can be found in the Refresh Firefox - reset add-ons and settings article.

Did this fix your problems? Please report back to us!

Unfortunately, your "More system details" does not list any plugins or extensions, so it is difficult to suggest the ones that you might want to disable or remove.

Try this:

(1) Disable ALL nonessential or unrecognized add-ons on these two tabs:

orange Firefox button (or Tools menu) > Add-ons > Plugins category
orange Firefox button (or Tools menu) > Add-ons > Extensions category

Restart Firefox.

(2) Run the Search Reset extension:

https://addons.mozilla.org/en-US/firefox/addon/searchreset/

Does that help? If the problem returns when you restart Firefox, you may need to manually remove a user.js file or external software, but let's come back to that.

You can also check for problems with preferences and try to rename or delete the prefs.js file and possible numbered prefs-##.js files and a possible user.js file to reset all prefs to the default values.

• http://kb.mozillazine.org/Preferences_not_saved
• http://kb.mozillazine.org/Resetting_preferences