If you have QuickTime installed on your PC you’ll need to uninstall it without delay. According to a blog post at Trend Micro, there are two zero day vulnerabilities related to QuickTime that Apple will not be patching because it is ending support for QuickTime on Windows.
It is never a good idea to use software that is no longer being supported, especially if it has known vulnerabilities. Uninstall QuickTime as soon as possible to protect your PC.
To check if you have QuickTime installed on Windows 10, right click your Start Menu icon and choose Programs and Features:
Look through the list of installed programs and if you come across QuickTime, Right-click the name and choose Uninstall.
If you have a different version of Windows, follow the tutorial at BleepingComputer on How to uninstall a program in Windows Vista, Windows 7 and 8.