Authorise a computer to play iTunes purchases
To play many purchases from the iTunes Store, you must authorise your computer using your Apple ID and password. (Authorisation helps protect the copyrights of the purchased items.)
You can authorise or de-authorise a computer at any time.
Authorise a computer to play iTunes Store purchases
You can authorise up to five computers (Mac, Windows or both) at a time. To play a purchased item on a sixth computer, you need to de-authorise another one. An iPod, iPhone, iPad or Apple TV doesn’t count as a computer.
In the iTunes app
on your PC, choose Account > Authorisations > Authorise This Computer.If requested, enter your Apple ID password to confirm.
De-authorise a single computer
Make sure you de-authorise a computer before you sell it or give it away.
In the iTunes app
on your PC, choose Account > Authorisations.Do one of the following:
De-authorise a computer: Choose De-authorise This Computer.
De-authorise a computer to play spoken programmes purchased from the Audible website: Choose De-authorise Audible Account.
De-authorise all authorised computers
If you forgot to de-authorise a computer you no longer own, and you have five authorised computers, you can de-authorise all your authorised computers at once. You can use this method once a year.
In the iTunes app
on your PC, choose Account > View My Account.On the right, click De-authorise All. If you don’t see this option, it’s because you have fewer than five authorised computers.
You can also authorise up to three computers to play items purchased from the Audible website (audible.com). Audible is a third-party company that sells audiobooks and other spoken programmes.
If you have trouble de-authorising a computer, see the Apple Support article Authorize your computer in iTunes.