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First, open > About this Mac, and see Version.
QuickTime disappeared on System Preferences with Mac OS X Leopard. If you have Snow Leopard, Lion or Mountain Lion, you have QuickTime Player X, and you need QuickTime Player 7 on your Mac to upgrade to Pro. See > http://support.apple.com/kb/HT3678
Then, to upgrade to Pro version, follow the steps of that link
The QuickTime app inside your Applications folder (and, probably on your dock) is QuickTime X, not QuickTime 7. To find and launch QuickTime, you must open the Utilities folder, which is inside your Applications folder. You can have both versions on your computer. QuickTime 7 has some functions that are not available in QuickTime X, and vice versa.