You can check if you still have the XML files of the default search engines including Google in the searchplugins folder in Firefox program folder.
If not then you need to reinstall Firefox.

Try to use the SearchReset extension to reset some preferences to the default values.

• https://addons.mozilla.org/firefox/addon/searchreset/

Note that the SearchReset extension only runs once and then uninstalls automatically, so it won't show on the "Firefox > Add-ons" page (about:addons).

Try to delete the search.json file and a possible search.sqlite file in the Firefox profile folder.

• http://kb.mozillazine.org/Profile_folder_-_Firefox

Firefox will rebuild the search.json file from the default search engines in the searchplugins folder in the Firefox program folder and the searchplugins folder in the Firefox profile folder.

Do a clean reinstall and delete the Firefox program folder before reinstalling a fresh copy of Firefox.

Download a fresh Firefox copy and save the file to the desktop.

• Firefox 20.0.x: http://www.mozilla.org/en-US/firefox/all.html

Uninstall your current Firefox version, if possible, to cleanup the Windows registry and settings in security software.

• Do NOT remove personal data when you uninstall your current Firefox version, because all profile folders will be removed and you will also lose your personal data like bookmarks and passwords from profiles of other Firefox versions.

Remove the Firefox program folder before installing that newly downloaded copy of the Firefox installer.

• It is important to delete the Firefox program folder to remove all the files and make sure that there are no problems with files that were leftover after uninstalling.
• http://kb.mozillazine.org/Uninstalling_Firefox

Your bookmarks and other profile data are stored in the Firefox profile folder and won't be affected by an uninstall and (re)install, but make sure that "remove personal data" is NOT selected when you uninstall Firefox.

If you keep having problems then also create a new profile.

• http://kb.mozillazine.org/Profile_folder_-_Firefox
• http://kb.mozillazine.org/Profile_backup

• http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Clean_reinstall

FIX Firefox 20.0.1 search not functioning.

Thanks for the tips. Turns out that the new updated version has some functions set differently. Most likely predicated on my old settings? Specifically under tools, you need to go to: options, privacy then select history "use custom settings for history"

If you select "Never remember history" the search function does not work. Nor does the page fully load up.

The security conscious can further select individual settings within the separate click-able boxes within the "custom settings for history" tab.