I have an iPhone 4 with the latest iOS 7.0.3. When I received a video clip (mov) in my email, there is a winmail.dat icon that said Tap to Download. When I tap and it would show the download progress. But when it's done, I can't see the video. If I tap or double tap on the winmail.dat icon, it would open an option for mail. I want to save it to my camera roll. How do you do that?