Rentals typically have a 24 or 48 hour viewing window, which means you only have 24/48 hours from the fist time you start streaming or downloading to complete the viewing. If you try to watch it after the 24/48 hour window, you'll receive a license error and you'll need to re-rent the title in order to obtain a new, valid license. Please note that you can keep an unwatched rental on your device or in your Library for up to 30 days. The license clock won't begin until the first time you start playing the content. You can find more information on licensing under the FAQ, "What is a License?"