In most cases, a clean install is not required when installing Flash Player.  The Flash Player installer will upgrade previous installs without having to uninstall first.  However, if you find you're running into problems or would like to downgrade to a previous version, the following steps should help.

Windows

1. Download the current uninstaller
   • Uninstaller for Windows
2. Close all browser windows and run the uninstaller
3. Restart Windows
4. Delete all remaining files and folders located in the following directories.  (tip: copy and paste these paths into the path bar in an Explorer window)
   • C:\Windows\system32\Macromed\Flash
   • C:\Windows\SysWOW64\Macromed\Flash
   • %appdata%\Adobe\Flash Player
   • %appdata%\Macromedia\Flash Player
5. Verify that the files “FlashPlayerCPLApp.cpl”, "FlashPlayerApp.exe", and "FlashPlayerInstaller.exe" in C:\Window\system32\ (for 32-bit systems) or C:\Windows\SysWOW64\ if you are using a 64-bit system, have been deleted.  If any of these files cannot be deleted, use Unlocker to remove them from your system.
   • Note that you may not see the .exe suffix on FlashPlayerApp.exe and FlashPlayerInstaller.exe, depending on your Explorer settings.

Macintosh

1. Download the appropriate uninstaller from the following page: Uninstall Flash Player | Mac
2. Close all browser windows, mount and run the uninstaller
3. Restart OS X
4. Delete all remaining files and folders locating in the following folders:

• \Library\Internet Plug-Ins\Flash Player.plugin
• \Library\Internet Plug-Ins\flashplayer.xpt
• ~\Library\Preferences\Macromedia\Flash Player\
• ~\Library\Caches\Adobe\Flash Player\

At this point, Flash Player should be fully removed from your system.  To download the most recent version of the Player for installation, please see these pages:

Recommended version of Flash Player

Where can I find direct downloads of Flash Player 10.3 for Windows or Macintosh?

Message was edited by: Pat Willener - added FlashPlayerApp.exe, FlashPlayerInstaller.exe