Google is the default search engine for the Search bar - add, change and manage search engines on Firefox and the default Internet Keyword search service for Location bar search in current Firefox versions. See the linked articles for resetting Google as the default.

You may first need to uninstall any toolbar or other add-on you may have installed recently that is making Firefox use the Ask search engine. See Disable or remove Add-ons and http://kb.mozillazine.org/Uninstalling_toolbars for more information.

P.S. If you are asking about going back to an older Firefox version because of the Google Toolbar, see Google Toolbar is no longer compatible with Firefox - Here are some alternatives for alternative solutions.

If you still want to use the Google Toolbar:

• See Install an older version of Firefox to go back to Firefox 3.6, which is the last version still being maintained with security and stability updates.
• See Re-enable add-ons that were disabled when updating Firefox to "force" disabled add-ons to work in your current Firefox version.

Thank you

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