The Department of Homeland Security is recommending Windows users uninstall QuickTime 7. https://www.us-cert.gov/ncas/alerts/TA16-105A This is because Apple ended support for Windows QuickTime on 4/14/16, no more Windows QuickTime updates will be released, and two vulnerabilities have already been published on Trend Micro’s Zero Day Initiative website.
Apple has been deprecating the 11 year old Windows QuickTime 7 for a while, and last January they killed the Windows QuickTime browser plug-in. This forced Window’s users to find another method for playing QuickTime content in their web browsers.
Windows QuickTime 7 can be uninstalled by navigation to Control Panels, then selecting Programs->Uninstall a program. Select QuickTime, then click Uninstall.
Windows QuickTime required for Windows Adobe CC
The Adobe Creative Cloud Support Team has announced that uninstalling Windows QuickTime 7 will break some features in the following Windows Adobe Creative Cloud apps: Photoshop, Lightroom, After Effects, and Premier Pro. “Unfortunately, there are some codecs which remain dependent on QuickTime being installed on Windows, most notably Apple ProRes. We […] have no estimated timeframe for native decode currently.” http://blogs.adobe.com/creativecloud/quicktime-on-windows
Windows Creative Cloud users should evaluate their workflow before uninstalling QuickTime 7. The fact that Apple has already killed the Windows QuickTime browser plug-in minimizes the risk to Windows users, preventing a simple drive-by exploit. The two known Windows QuickTime vulnerabilities would require the attacker to convince the victim to download a maliciously crafted file and opened it in QuickTime.