Actually, I did NOT have my itunes account set.
However, I set it, and it did not solve the problem.
Airplay is enabled. I use it all the time. Just doesn't work with Cars 2. Cars 2 is actually the first movie that I ever bought from Apple, so it might be all movies, I don't know. But everything else works fine with airplay.
Long time reader joined just to say I'm having the same issue with Cars 2. Downloaded on my iPhone 4, will not play on apple tv no matter what. I'm able to use the remote app, stream videos I've taken from camera roll, and tv shows I have on the phone, but the movie won't play.
Apple TV is up to date, I completely reset it, tried the download a free show trick that was on the apple discussion forums and that didn't work....I'm at a total loss. Is it possible it's a restriction in the movie itself?
I'm having the exact same issue. Bought Cars 2 on my iPad2, trying to Airplay it to my Apple TV2, and I'm getting the "not authorized to play this content" message. Everything else is playing just fine, including recent episodes of TV shows I've purchased. I haven't tried downloading any more movies to my iPad2, though. I updated all software for Apple TV2 and iPad2 and rebooted everything. Apple support stopped responding to me.