I have an iPhone 4S that currently runs iOS 6.1.3. Recently, it stopped playing video with QuickTime player. I tried playing a Collegehumor video on safari which worked a couple days ago. No matter if I open it on my Facebook app or on Safari, I get a message stating "The operation could not be completed." My phone isn't jailbroken, so does anyone know what I should do? If I play a video on the Youtube app it works fine, though."