iTunes 12.2 doesn't open Quicktime

Hello.

I'm on a MacBook Air - 2014 model with OS X Yosemite 10.10.4 installed.

I updated iTunes to the most recent version (12.2). Now, whenever I want to open a quicktime file with it (for example a video podcast or a trailer) I get an error message saying the following: 'This movie requires QuickTime; this application isn't supported by this version o iTunes' (Sorry if the translation is bad: my language is Portuguese).

Anyone knows why this is happening to me?!

Everything was updated yesterday!!! OS X, Garageband & iTunes...

Thank you.