Since April last year, Trend Micro have been urging Windows users to uninstall Quicktime because they had found two major vulnerabilities in the software and Apple had announced they would no longer be issuing security updates for it. This poses a problem for animators like myself since this particular piece of software is what enables us to playblast in the highly efficient h.264 codec.
To get the codec back after having uninstalled Quicktime, simply start the installation process again (the program can still be downloaded on Apple’s website) but at the point of where it asks the setup you want, choose “Custom“.
Then make sure to uncheck the “QuickTime Player” option. The player is the part that has the security vulnerabilities. The Essentials part contains the codec.