Do a clean (re)install:

• Download a fresh Firefox copy and save the file to the desktop.
• http://www.mozilla.com/firefox/all.html
• Uninstall your current Firefox version and remove the Firefox program folder before installing that copy of the Firefox installer.
• Don't remove personal data if you uninstall the current version.
• 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.

Your bookmarks and other profile data are stored elsewhere (not in the Firefox program folder) and won't be affected by a reinstall, but make sure that you do not select to remove personal data if you uninstall Firefox.

Thanks my friend it worked perfect

You're welcome.

This can happen if the updater wasn't able to update all files (some may have been locked by security software) and some older files were left.

Many thanks cor-el. Found old installation file, removed this and followed your instructions and all OK now.

I'm trying to print a shipping label from USPS and keep getting the "can't find C:\Program Files (x86)\Mozilla Firefox\Eula.exe" message.

I've tried doing your clean re-install three times but am still having the same problem. I made sure to delete the Mozilla folder and did an advanced search to delete any stray files.

Any suggestions?

Edited to Add: After doing the re-installs I searched in the Mozilla folder and there is no eula.exe file.

Also, now all of my Bookmarks are missing. How do I restore those?