Quicktime Won't Open

Double-click on the "Activity Monitor" program to launch it--the program is located inside of the "Utilities" folder that is inside of the "Applications" folder. Locate "QuickTime Player" from beneath the "Process Name" column in the window that appears. Click once on "QuickTime Player." Click the "Quit Process" button at the top left of the window. Click "Quit" in the confirmation window that appears. Quit the "Activity Monitor" program. Restart the Mac.

Double-click on the main hard drive to open its window. Double-click on the "Library" folder to open its window. Scroll down to the "Preferences" folder. Double-click on the "Preferences" folder to open its window. Drag the "com.apple.QuickTime" file to the Trash. Empty the Trash. Close all of the open windows by clicking their red buttons in the upper left corner. Restart the Mac.

Double-click on the "Disk Utility" program that comes with the Mac's OS X operating system--the program is located inside of the "Utilities" folder inside of the "Applications" folder. Click on the icon of the main hard drive in the left column of the program's main screen. Click the "Repair Disk Permissions" button at the bottom of the program's screen. Quit the program after the text in the center column of the program stops scrolling. Restart the Mac.

Click "Start," "Run." Type "Regedit" without the quotes in the command line window that appears. Press the "Enter" key. Click on the "QuickTime Player" icon that is in the left column of the window that appears. Select all of the files in the column to the right by clicking "Cntrl+A." Right-click in the column. Select "Delete" from the pop-up menu. Click "Yes" on the confirmation window to make it disappear. Close the window that is still open on the desktop by clicking the red "X" button in the upper right corner. Download and install the QuickTime Player program again. Restart the PC.

Go to "Start," "My Computer," "Control Panel." Click on "Add or Remove Programs" in the window that appears. Click on "QuickTime Player" in the window that appears. Click the "Change/Remove" button on the window. Click "OK" in the confirmation pop-up window when it appears. Close the "Finished" pop-up window by clicking its "OK" button. Close the window that is still on the desktop by clicking the red "X" in the upper right corner. Download and install the QuickTime Player program. Restart the PC.

Go to "Start," "My Computer." Double-click on the "C" drive in the left column to expand a file list beneath it. Double-click on "Documents and Settings" to expand a file list beneath it. Double-click on your username to expand a file list beneath it. Double-click on "Application Data" to expand a file list beneath it. Double-click on "Apple Computer" to expand a file list beneath it. Click once on "iTunes." Click one of the two "Preferences" folders in the right column. Right-click on the folder and select "Delete" from the pop-up menu. Repeat this procedure with the other "Preferences" folder. Close the window by clicking the red "X" in the upper right corner. Restart the PC.