My father has rented a move on iTunes, but on his old computer (which can't cope and crashes when he tries to play it). He's now on a newer computer, and logged into iTunes with the same account, but we can't find the rented movie.
I can confirm that the following works:
- I downloaded a movie on my pc-laptop
- I moved it via my network share, added it to the library on my macbook
- It was visible as rented there but could not be watched (authorized to another computer)
- Then I unauthorized the computer I downloaded it on and it worked on my macbook
You should move your dad's entire iTunes library from his old computer and merge it with the iTunes library on his new computer.
Read Apple's technical support documentation article: iTunes: How to move your music to a new computer
You need to log into the other computers iTunes with the same iTunes username and password. Go to the "store" menu bar item and click "Check for available downloads".
This will bring up movies you have rented with the same account - as long as they are still valid.
You can manually copy the movie.
Right-click on the file and select Show in Finder then copy the movie onto a flash drive and move it to the new computer.
When on the new computer - opening the file should open iTunes. Since it's connected to the same account, the movie should play.
The computer is already authorised. It appears that it is the 'file' that needs to be authorised to play on another computer