I rented a movie on iTunes from my MacBook Air but when I try to sync to my iPad it says could not transfer to the iPad because it has been transferred to another device.
If I remember correctly, you can move the Movie from iTune to iPad.
Assuming that the movie has not been transferred to another device ....When weird stuff like this happens to me the first thing that I do is to quit everything and start all over again.
Quit iTunes, restart the iPad, restart the MBA and then try again.
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