Hi, I am trying to transfer my rented movie to my iphone

Hello there, lorettafromqld.

The following Knowledge Base article is a great resource on transferring rented content to your iOS device:

How to rent a movie from the iTunes Store on your computer

http://support.apple.com/kb/HT1390

To rent movies from the iTunes Store on your computer

1. In iTunes on your computer, click iTunes Store.
2. In the iTunes Store, find a movie you want to rent.
3. Click Rent. Your rental should begin to download immediately.

Once the rental is downloaded, you can watch it on your computer or transfer the rental to a supported iPod, iPhone, iPad, or Apple TV (1st generation):

1. Connect the device and select it in iTunes.
2. Click the Movies button.
3. Select the movie, and then click Move.
4. After all movies have been moved, click Apply in the lower-right corner of iTunes.

You must be connected to the Internet to transfer a rented movie.

Additional Information

• After you transfer a rental, it is removed from your iTunes library.
• You can move the movie between devices as many times as you wish during the rental period, but the movie can only be played on one device at a time.
• Pairing needs to be configured to transfer a rental to Apple TV (1st generation).

For information about movie rental expiration and viewing limits and for more information about iTunes Store movie rentals, read the article iTunes Store: Movie rental frequently asked questions (FAQ).

Thanks for reaching out to Apple Support Communities.

Cheers,

Pedro.