You may see some warnings or alerts about the download, but is a safe site. You will want to use the first link to download QuickTime Alternative 3.2.2.

Click here to go directly to the download page for QuickTime Alternative. If you want to uninstall QuickTime, you can replace it with the free QuickTime Alternative. Both of these versions will still be able to play WMV or MPEG videos, but they will not be able to play QuickTime files (MOV or MP4). ProPresenter 4 and ProPresenter 5 may not work properly without QuickTime being installed on your computer. We rebuilt our render engine to be fully self-contained and not rely on third-party software like QuickTime. If you are using ProPresenter 6 then you no longer need QuickTime. The main basis of the render engine for ProPresenter 4 and ProPresenter 5 is built around QuickTime, thus you will need to keep QuickTime installed on your machine for ProPresenter to work properly. While QuickTime is still available for download from Apple, the program itself is no longer being updated or supported. Due to various known vulnerabilities in QuickTime for Windows, Apple made the choice to end support for their product on April 14, 2016.

Windows 8.1 quicktime download