The Automatically update search engines may add new search engines to Firefox as they become available. While I've never had it change the default search engine that Firefox uses, I have had previously deleted search engines get added back to Firefox.

If you uncheck the Automatically update search engines option from the Firefox settings page, that should prevent this from happening in the future.

Hope this helps.

I only have one option for a search engine and that is Yahoo. I want to go back to using google as my default search engine but that option does not seem to exist in my settings and preferences.

Hi IVR4, some users have encountered a problem with built-in search engines vanishing from their Options/Preferences page. Have you already tried using the "Restore" button here:

• Mac: "3-bar" menu button (or Firefox menu) > Preferences
• Windows: "3-bar" menu button (or Tools menu) > Options
• Linux: "3-bar" menu button (or Edit menu) > Preferences
• Any system: type or paste about:preferences into the address bar and press Enter/Return to load it

In the left column, click Search, and then on the right side, scroll down to the bottom of the "One-Click Search Engines" box and try the "Restore Default Search Engines" button.

Does Google come back?

If not:

You may need to remove a Firefox settings file and let Firefox regenerate it. Here's how:

Open your current Firefox settings (AKA Firefox profile) folder using either

• "3-bar" menu button > "?" Help > Troubleshooting Information
• (menu bar) Help > Troubleshooting Information
• type or paste about:support in the address bar and press Return

In the first table on the page, on the Profile Folder row, click the "Show in Finder" button. If Finder highlights an icon with a semi-random name like a1b2c3d4.default-release, double-click it to display the contents of that profile folder.

Leaving that window open, switch back to Firefox and Quit out (for example: Firefox menu > Quit).

Pause while Firefox finishes its cleanup, then rename search.json.mozlz4 to something like searchOLD.json.mozlz4.

Start Firefox back up again. It should rediscover the built-in search engines and allow you to check and modify the default.

Does that work?

I should add that Yahoo isn't a built-in search engine, so one of your add-ons might be responsible for you getting results on Yahoo.

You can view, disable, and often remove unwanted or unknown extensions on the Add-ons page. Either:

• Command+Shift+a (Windows: Ctrl+Shift+a)
• "3-bar" menu button (or Tools menu) > Add-ons
• type or paste about:addons in the address bar and press Enter/Return

In the left column of the Add-ons page, click Extensions.

Then cast a critical eye over the list on the right side. Any extensions Firefox installs for built-in features are hidden from this page, so everything listed here is your choice (and your responsibility) to manage. Anything that mentions search, or that you just do not remember installing or why? If in doubt, disable (or remove).

Any improvement?