Install Re-install or Upgrade Firefox

Background

Mozilla has not yet provided an automatic upgrading process for Firefox. Nothing like Microsoft provides for Windows and Internet Explorer. In particular, security updates require that you install a new version of Firefox each time Mozilla fixes a vulnerability.

Current versions of Firefox now allow incremental updates. You'll be notifies when an update is available.

It's not hard to (re)install or upgrade Firefox, but to be successful you sometimes need to know a little bit more than what Mozilla.org tells you. That's what this page is for. I hope it removes any mystery for you.

Firefox (and other Mozilla programs) do not make entries in the Windows registry. That's wise, I wish that more programs worked that way. It means Firefox does not write to the Windows registry. There is never any clean up to do after Firefox. That makes it much simpler to keep your Firefox installation neat and up to date.

Software developers have access to the Windows registry to store hundreds, even thousands of settings for their programs. Some of them do. It was a huge mistake for Microsoft to set things up that way, but that's another story. I think it's fortunate that Mozilla doesn't use the Registry at all.

The Firefox installer

You install Firefox in much the same way you install most other programs -- double-click the install file >> accept or change options >> tell it to proceed -- you know the drill. After you get it set up, the install wizard does three simple things. To install Firefox it:

  1. Creates the program files folder and sub-folders, and copies most of the Firefox files to it. The default program folder location will be something like
    C:\Program Files\Mozilla\Firefox 1.0.7\
  2. Creates the profile folder and sub-folders and copies the rest of the firefox files there. The profile folder location will be something like:
    C:\Documents and Settings\{your user name}\Application Data\Mozilla\Firefox\Profiles\d4cr8lbx\ The name of your own profile folder will be some random number that is different from the one shown here.
  3. Creates the Firefox shortcuts (icons) and copies them to the Start menu (under programs).

Note: When you start Firefox the first time it creates some more files and folders, but they all are located somewhere in either the profile folder or the program folder. If a different user logs on to Windows and starts Firefox, they will get their own profile.

Installing and re-installing Firefox

I wrote these instructions a long time before there were good instructions for installing Firefox. They are still valid, but you may be better served by the official instructions. Look for "Installing Firefox" on the Firefox Help & Tutorials page.

When I install Firefox for the first time, I choose the "Custom Installation" option and direct the wizard to install the program in:

C:\Program Files\Mozilla\Firefox\

Note that I do not include 3.1 or anything like that after Firefox. More on the reason later.

When I subsequently reinstall or upgrade Firefox I follow this method:

  1. Make sure that Firefox and all Firefox utilities like the Bookmark Manager, Download Manager, etc., are closed.
  2. Back up both the program folder and the profile folder. (You should be backing up the profile on a regular basis, but this last minute backup is important.
  3. Delete everything in the program folder -- C:\Program Files\Mozilla\Firefox\ -- except the "plugins" and the "searchplugins" folders. The screenshot shows what I select for deletion. Do not worry about the extensions folder -- it will be regenerated when Firefox is started again.
  4. Now I am ready to run the installation file. I select the "Custom Installation" option again. The wizard will probably indicate -- C:\Program Files\Mozilla\Firefox\ -- as the installation folder. If not, I browse there to change it to that location.
  5. Then I proceed with the installation until the wizard asks if I want to create shortcuts in the Start menu, on the Desktop, etc. I uncheck all of them (because the old ones will still work, and I have previously moved them to where I want them. I don't want duplicates.
  6. That's it. I start Firefox, and everything -- except perhaps some extensions that are no longer compatible -- (usually) works as before.

Note that I do not uninstall the old version of Firefox before installing the new version. Yes, I know that is not the recommended way to do it, but my method has virtually the same effect. More on my reasons below.

My reasons

  1. I do not uninstall Firefox (or delete everything in the Firefox program folder) because I would need to reinstall my favorite search plugins and probably some of my other plugins.
  2. I keep the program folder -- C:\Program Files\Mozilla\Firefox\ -- the same so that the Firefox shortcuts in the Start menu and, more importantly, my "DropMyRights" shortcuts for Firefox will still work.

If all else fails

Bad things happen to good people. If Firefox doesn't work after you upgrade or reinstall, it's still relatively easy to get it going again. Here's the most straightforward way:

  1. Close Firefox and any Firefox utilities.
  2. Delete the profile directory, pruning back to C:\Documents and Settings\{your user name}\Application Data\Mozilla\Firefox\ or even C:\Documents and Settings\{your user name}\Application Data\
  3. Delete the entire contents of the Firefox program directory.
  4. Install Firefox. This will be completely fresh installation.
  5. Start Firefox. Firefox will create a new profile folder for you.
  6. Close Firefox.
  7. Copy the "bookmarks.html", "prefs.js", "cookies.txt", "key3.db" and "signons.txt" files from your profile folder backup to your new profile folder, replacing any that are already there. [reference]
  8. Firefox should now be much like it was before the troubles began, except that you will need to reinstall your Firefox extensions.