Browsers forum: READ ME: Browser Tips and Tricks...

NOTE #1: These instructions are designed for those running Windows 2000/XP/Vista/7; some differences may apply.
NOTE #2: This will delete all Firefox extensions, themes, and settings. It should be used only as a last resort.

Closing Firefox:
1.) Press Ctrl + Shift + Esc (or Ctrl + Alt + Delete) to view Windows' Task Manager.
2.) On the Processes tab, make sure firefox.exe is not listed.
3.) If you find any instances open, right-click it and select End Process.
4.) Click the "X" to close Windows Task Manager.
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Backing up your bookmarks/favorites:
1.) In Firefox, press Ctrl + Shift + B. The Bookmarks Manager will appear.
2.) Go Import and Backup ⇒ Backup and save the file to your Desktop.
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Uninstalling Firefox:
1.) Go Start ⇒ Control Panel and click the 'Uninstall' option. (Exact name varies by OS.)
2.) Select Mozilla Firefox and click Remove/Uninstall.
3.) Follow the prompts of the uninstaller. If asked to delete all related files, check the box to do so.
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Removing the Remnents of Firefox:
1.) Double-click My Computer and go to C:\Program Files.
2.) Delete the Firefox (or "Mozilla") folder.
3.) Go to the Firefox AppData folder (see location below).
4.) Delete all of the files and folders in that folder.
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Firefox AppData folder:
1.) The location of this folder varies based on your operating system.
2.) Note that "username" is usually your Windows username.
3.) The Application Data/AppData folder is hidden by default. To view it, you must go Tools ⇒ Folder Options in Windows Explorer, select the View tab, and select show hidden files and folders before proceeding. (If the Tools menu is 'missing,' press the Alt key to temporarily display it.)

Windows Vista/7:
C:\Users\username\AppData\Roaming\Mozilla\Firefox\

Windows 2000/XP:
C:\Documents and Settings\username\Application Data\Mozilla\Firefox\

Windows 95/98:
C:\WINDOWS\Application Data\Mozilla\Firefox\

Linux:
~/.mozilla/firefox/

Mac OS X:
~/Library/Application Support/Firefox/
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Reinstalling Firefox:
1.) If you have not already done so, download the latest version of Firefox.
2.) Run the Firefox installer you downloaded and follow the on-screen prompts.
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Restoring your favorites/bookmarks:
1.) Launch Firefox and press Ctrl + Shift + B. The Bookmarks Manager will appear.
2.) Go Import and Backup ⇒ Restore ⇒ Choose File and select the previously-saved file from your Desktop.
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Finishing Touches:
1.) Re-download the desired extensions and themes again, one at a time.
2.) Modify your settings (Tools ⇒ Options) any way you like to customize your browsing experience.


John

Note: This post was edited by forum moderator to update and clarify instructions on 01/22/2011 on 10:33 PM PT