Currently Being ModeratedSep 26, 2013 2:01 PM (in response to JGSA1)
Thank you for providing the details of the issue you are experiencing with the movie rental purchased from the iTunes Store. It sounds like you are doing everything correctly, and I understand your frustration with the continuous prompts to authorize the computer.
I recommend the following the steps in the following article for an issue like this:
Thank you for using Apple Support Communities.