Please Try safemode as an initial troubleshooting step

• Diagnose Firefox issues using Troubleshoot Mode

If safe mode does not help checking for malware may be the next step

• Troubleshoot Firefox issues caused by malware

Try Firefox Safe Mode to see if the problem goes away. Firefox Safe Mode is a troubleshooting mode that turns off some settings and disables most add-ons (extensions and themes).

(If you're using an added theme, switch to the Default theme.)

If Firefox is open, you can restart in Firefox Safe Mode from the Help menu by clicking on the Restart with Add-ons Disabled... menu item:


If Firefox is not running, you can start Firefox in Safe Mode as follows:

• On Windows: Hold the Shift key when you open the Firefox desktop or Start menu shortcut.
• On Mac: Hold the option key while starting Firefox.
• On Linux: Quit Firefox, go to your Terminal and run firefox -safe-mode
  (you may need to specify the Firefox installation path e.g. /usr/lib/firefox)

Once you get the pop-up, just select "'Start in Safe Mode"

If the issue is not present in Firefox Safe Mode, your problem is probably caused by an extension, and you need to figure out which one. Please follow the Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems article to find the cause.

To exit Firefox Safe Mode, just close Firefox and wait a few seconds before opening Firefox for normal use again.

When you figure out what's causing your issues, please let us know. It might help others with the same problem.

Thank you.

Problem still exists in Firefox Safe Mode. I am certain that the problem commenced with the upgrade to 28.0, so am extremely doubtful that it is an effect of malware - I am protected by Norton Internet Security which operates from start up. What now?

You can try to open a new window to see if the location bar works better.

Create a new profile as a test to check if your current profile is causing the problem.

See "Creating a profile":

• https://support.mozilla.org/kb/profile-manager-create-and-remove-firefox-profiles
• http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Profile_issues

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over the problem

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

Do a clean reinstall and delete the Firefox program folder before (re)installing a fresh copy of the current Firefox release.

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

• Firefox 28: http://www.mozilla.org/en-US/firefox/all.html

If possible uninstall your current Firefox version to cleanup the Windows registry and settings in security software.

• Do NOT remove "personal data" when you uninstall your current Firefox version, because this will remove all profile folders and you lose personal data like bookmarks and passwords including data in profiles created by other Firefox versions.

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

• (32 bit Windows) "C:\Program Files\Mozilla Firefox\"
• (64 bit Windows) "C:\Program Files (x86)\Mozilla Firefox\"

• 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 personal 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.

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

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

First of all Check your Firefox search bar works ok, and that it is set to a sensible option. Many users probably do not realise that the Search bar search engine is used for all the Firefox searches now, including the addressbar search.

Obviously this is not affecting everyone with Firefox 28. It is in fact a pretty rare problem, and I do not know what is causing it. All I can do is suggest a process of elimination.

If the problem was only after update there must still be some other factor involved.

No antimalware product is perfect. It is still worth trying scans with multiple and up-to-date anti malware tools.

Next try a process of elimination (Probably best in this order, and check after each step) Try

1. In safe mode and with all plugins disabled.
   • Diagnose Firefox issues using Troubleshoot Mode
   • Disable or remove Add-ons
2. A new profile. Or resetting Firefox.
   • Refresh Firefox - reset add-ons and settings
   • Profile Manager - Create, remove or switch Firefox profiles
3. A clean reinstall
   • Troubleshoot and diagnose Firefox problems'_5-reinstall-firefox
     That involves deleting the Firefox Program folder contents. ( NOT the profile)
     It is probably worth scrolling and reading the whole article.

Some similar threads worth watching

• Current address in address bar clears for no reason /questions/991296
• (solved but a different symptom /questions/992017 - there also will be malware and redirect problems listed)
• My address bar won't search for anything, redirects it? /questions/989568

Researched all the material you suggested and successfully created new profile and transferred relevant files to it. Appears to work o.k. Thank you all.

Good to hear it works again.

If you need to transfer anything between profiles have a look at

• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox#Suggested_profile_contents_to_transfer

It is however probably easiest to reinstall addons one at a time. It is often the bookmarks and passwords that will be wanted in the new profile. If you used the Firefox reset method those will have be retained.