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).

You can 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 value.

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

I have used the SearchReset extension and it has fixed the search bar at the top right hand side of my screen. However the search bar in the middle of my screen under the large Firefox icon still does not have a search engine allocated and is not allowing me to search. I have had a look at the last 2 links you provided but am really unsure on what to do next

If you delete the prefs.js file in the profile folder then all prefs will be reset to their default value.

You can use this button to go to the Firefox profile folder:

• Help > Troubleshooting Information > Profile Directory: Show Folder

Current Firefox versions use the default search engine (pref: browser.search.defaultenginename) to set the search engine that is used on the about:home page.

Check the browser.search.defaultenginename pref on the about:config page and make sure that it is set to the default value Google.

• browser.search.defaultenginename

Currently selected search engine:

• browser.search.selectedEngine

• http://kb.mozillazine.org/about:config

Which security software (firewall, anti-virus) do you have?

Some security software has virtualization or sandbox features that may cause problems by protecting and restoring files in the Firefox profile folder.

I typed in browser.search.defaultenginename

 and it found

browser.search.defaultenginename;Google
browser.search.defaultenginename,S;Google
sweetim.toolbar.previous.browser.search.defaultenginename;Google

I changed all 3 to Google and now everything is working fine. Thank you for your assistance