Learning how to uninstall Mozilla Firefox on a PC is a little trickier than it appears. If you're simply using the Add and Remove Programs tool to uninstall Firefox, you could run into errors when you try to upgrade Firefox or install other Internet browsers. That's because some files remain on your PC even after you uninstall the software itself.
There are two steps to uninstalling Firefox. The first step is actual process of uninstalling the Firefox program. The second and crucial step is to remove your user data and settings.
Uninstalling Firefox Software
Be sure to exit Firefox and close all of its windows, including the Downloads window. Choose Exit from the Firefox File menu rather than clicking the X in the corner, as closing the window still leaves Firefox running in the background
You'll lose your bookmarks and add-ons when you uninstall Firefox. If these are valuable to you, be sure to write them down before you begin the uninstallation process.
To remove any plug-ins or other add-on files and their folders, which may not have been removed during the uninstall process, you can manually delete the Firefox installation folder. The default location is C:\Program files\Mozilla Firefox. This folder can be dragged into the Recycle Bin and deleted.
Removing User Data and Settings
Uninstalling Firefox does not remove your personal information, such as bookmarks, passwords and cookies. To do a clean uninstall, you should remove these files. These may be located in a hidden folder in Windows. You'll need to enable hidden folders to find the files, and the process is slightly different for XP/2000 and Vista.
In Windows Vista, choose Start Search from the Start Menu, then click the Folder Options shortcut. Click the View tab and select Show Hidden Files and Folders.
In Windows 2000/XP, open My Computer. Click the Tools menu and select Folder Options. Click the View tab and select Show Hidden Files and Folders.
The default profile folder locations for Firefox data are as follows:
You'll find default temporary data in these locations:
Delete these files by dragging them into the trash. Be careful to delete the files and not their enclosing folders, or you could cause problems with your Windows operating system.
With thousands of Firefox add-ons available, choosing which ones to install can be a real challenge. Here are five free add-ons that are must-haves for all users.
Wondering how to install Firefox plugins? If you've got an active Web connection, you'll find everything you need in the Tools heading of the Firefox browser.