If you have problems syncing a video in iTunes on PC
If iTunes tells you that a video wasn’t synced because it can’t be played on your device, you can convert it to a version that’s optimized for your device.
You can convert most videos to work with iPhone, iPad, iPod, or Apple TV.
In the iTunes app on your PC, choose Movies from the pop-up menu at the top left, then click Library.
Select the video you want to convert.
Do one of the following:
Choose File > Convert > Create iPod or iPhone Version.
Choose File > Convert > Create iPad or Apple TV Version.
Converting a video can take several minutes to several hours, depending on your computer and the length and content of the video.
The original video remains in your iTunes library.