OK I will try to help. I will first of all give a rather long-winded explanation.

Just simply uninstalling and re-installing Firefox often does not fix problems. Please try to follow the instructions here, and then post back to say how you get on or if you encounter problems or need further information.

There is a special method, we usually refer to as a clean reinstall that we sometimes need to ask users to try, if we think some files may be corrupt. Usually installing Firefox on Windows is fairly straightforward.

Unless we ask you to do a clean reinstall there is no need to do any uninstalling, and you should certainly not try to use uninstalling tools. The Firefox profile holds things like your settings and bookmarks, that should usually be left as it is unless we say otherwise because you probably want to keep things like your bookmarks.

So what do you need to do now

You should now do the clean install involving deleting the program files. Do NOT try to delete the profile files. Firefox will either find those itself if you are lucky, and use them. If it doesn't we may be able to help you find and use them please follow these instructions

To do a Clean Install This means you remove your Firefox program files and then reinstall Firefox. This process does not remove your Firefox profile data (such as bookmarks and passwords), since that information is stored in a different location.

To do a clean reinstall of Firefox, please follow these steps: Note: You might want to print these steps or view them in another browser.

1. Download the latest Desktop version of Firefox from mozilla.org (or choose the download for your operating system and language from this page) and save the setup file to your computer.
2. After the download finishes, close all Firefox windows (or open the Firefox menu and click the close button ).
3. Delete the Firefox installation folder, which is located in one of these locations, by default:
   • Windows:
     • C:\Program Files\Mozilla Firefox
     • C:\Program Files (x86)\Mozilla Firefox
   • Mac: Delete Firefox from the Applications folder.
   • Linux: If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it - see Install Firefox on Linux. If you downloaded and installed the binary package from the Firefox download page, simply remove the folder firefox in your home directory.
4. Now, go ahead and reinstall Firefox:
   1. Double-click the downloaded installation file and go through the steps of the installation wizard.
   2. Once the wizard is finished, choose to directly open Firefox after clicking the Finish button.

More information about reinstalling Firefox can be found here.

WARNING: Do not use a third party uninstaller as part of this process. Doing so could permanently delete your Firefox profile data, including but not limited to, extensions, cache, cookies, bookmarks, personal settings and saved passwords. These cannot be easily recovered unless they have been backed up to an external device! See Back up and restore information in Firefox profiles.

lThis does not help since I have been doing all those steps you instructed at least 10 or more times! Every time the setup run almost finished, as soon as I click "finish" button, the message "profile is missing or inaccessible" appeared, and that's the end of it!!! No firefox whatsoever! I found a file on my desktop named "Old Firefox data" stamped the time i had the crash and stopped the "restoration" process. Here is the part that I forgot to mention: After the final crash, there was a dialog for restoration, I clicked on it, but foolishly did not let it finish, and clicked cancel because it was taking a little long, I was totally ignorant about computer processing complexity!!! In that "old firefox data" file, I saw "bookmarkbackups", "extensions" etc... Many many files ... Where do I go from here, it there is a way ? Thank you for any help that you can provide!

I think the clean install may fix this issue. I would need to try that myself to check. But there is another method to fix this.

Find the fileprofiles.iniand rename it to profiles.ini.old (In Windows it may show as profiles) and will be located in

%APPDATA%\Mozilla\Firefox

• Please See http://kb.mozillazine.org/Profiles.ini_file

Now if you start Firefox it should start up with a brand new profile. It should not fail with any profile missing message. If Firefox does not start you will have to try the Clean install method as detailed in my last post. Please also record the exact error message you see.

Please keep the folder & files that you have on the desktop. This is a backup copy of your profile created by the Firefox Restore, you will need that to get back your bookmarks and other data. Please see

• Refresh Firefox - reset add-ons and settings <== This explains the Refresh option you tried, then aborted.
• Recovering important data from an old profile <== This explains how to get back bookmarks and data. In your case from the backup profile on the Desktop

This is an even easier method. Use Winkey + R to get a run dialogue.

Type (or paste)

firefox.exe -P

That will open the profile manager. Then create a new profile and use the profile manager to start Firefox.

As explained in

• How to run Firefox when your profile is missing or inaccessible_profile-was-deleted ==>
  • Profile Manager - Create, remove or switch Firefox profiles

WOW, Thank you so much for your help! I got firefox to open after I tried to create a new profile through firefox profile manager, but somehow it gave it a different name than profile.ini as you indicated. I still do not have normal firefox operation as I used to before all this troubles but I got further than before with your help! I got "firefox start page" and could open yahoo.com to test, so that is a great progress, I THANK YOU SO MUCH! I will continue to follow your instructions to see if I can get it to fully resolved then will report back, THANK YOU SO MUCH again!

Great.

Forget about the profile.ini comments I made. That was a method I usually use but the profile manger is simpler.

Now you will need to consider Recovering important data from an old profile

When you copy files it is a good idea to do it one file at a time then test the result. Try with the most important files first. The exception is if you have passwords you need to copy the matched pair of files.

Passwords
Your passwords are stored in two different files, both of which are required:

• key3.db - This file stores your key database for your passwords. To transfer saved passwords, you must copy this file along with the following file.
• logins.json - Saved passwords.