JUst happened to me as well. Rented Gone Baby Gone. Its in my itunes Media-Movies folder but can not open it with iTunes or Quicktime.
I've been charged as well.
Rented it via my laptop, was going to watch it on Apple TV. It is not in my Rentals on iTunes on the Laptop or Apple TV. Need a solution now. Ruining my nights plan. Macbook Pro Retina 10.7.5
I tried downloading initially I rented the SD version which I had issues with. I then Rented the HD version of the video & it worked.
I then emailed email@example.com, and explained the issue & asked for a refund. I got a response in less than 24 hours in which they gave me a no nonsense apology & full refund. Just be nice in the email with please & thank yous.
Best of luck
Any updates on this? I'm having the same issue. Just reinstalled OS X on my MacBook Pro, copied back my iTunes Media folder. All is good, except the Move Rentals button is missing from the sidebar. The movie I rented a few weeks ago is in the iTunes Media folder, too. (It shows up under phone/movies when my iPhone is connected...so it sees it for transfers.)
Just rented another movie to see if it would force the buttton to appear, but no go! The new movie is in the iTunes/Movies folder as well.