Q: iTunes cannot play a movie on my Mac !!

Hi anaghibi,

I understand that you are having an issue with playing back a rental that you got from the iTunes Stores. To get this sorted out, your best bet would be to report the problem to the iTunes Store. Take a look at the article below to walk you through this to get you back to playing that rental. 

Report a problem with an item purchased from the iTunes Store, App Store, Mac App Store, or iBooks Store
https://support.apple.com/en-us/HT204084

Have a good day