Performing a clean install removes any old components from the Mac version of the Player which may still be on your system, including the Player's preferences file. This will help verify that your Player is correctly installed and eliminate possible errors due to older libraries, and other components in use.
To delete all Player components from your Macintosh, perform the following steps:
Now that all possible older files have been deleted, reinstall the Player by double clicking on the installation file. If you no longer have the previously downloaded copy of the installer, you will need to redownload.
Apple recommends that you rebuild the desktop file after you install new software. To rebuild the desktop file, hold down the "Command" and "Option" keys while you restart the computer. Keep the keys held down until you see an alert reading "Are you sure you want to rebuild the desktop file on the disk "nameofhardrive"?" Release the keys and click "Ok". This process may take several minutes.