You can authorise your computer to play your purchases, deauthorise a computer from accessing purchases, and check how many authorised computers you have.
What you need to know about authorising your computer
Authorise or deauthorise your Mac
Authorise or deauthorise your Windows PC
You can authorise up to five computers at a time to play your Apple Account purchases.
Each computer you authorise counts as one authorisation – even if you authorise the same computer multiple times.
If you have five authorised computers and want to authorise a new computer, you'll need to deauthorise one of your computers.
You can only authorise a computer that you have access to. You can't authorise a computer using another computer or an iPhone or iPad.
After you authorise your computer in any Apple app, you can access all of your Apple Account purchases in other Apple apps.
After you authorise your computer, your computer is associated with your Apple Account for purchases. Other devices – like iPhone and iPad – don't count towards your authorised computer limit. However, these are associated with your Apple Account for purchases. Find out how to view your associated devices.
Use the Apple Music or Apple TV app to authorise or deauthorise your computer, and to check your authorised computer count.
Open the Apple Music app or Apple TV app.
From the Account menu in the menu bar, choose Authorise This Computer or De-authorise This Computer.

Sign in to your Apple Account. Forgot the email address or phone number that you use with Apple Account?
Click Authorise or De-authorise.
Open the Apple Music app or Apple TV app.
From the Account menu in the menu bar, choose Account Settings.
Sign in to your Apple Account. Forgot the email address or phone number that you use with Apple Account?
Scroll down, then look next to Authorised Devices to see how many computers are authorised.
You have to deauthorise all of your computers, then authorise each computer that you have again. You can only deauthorise all computers once a year.
Open the Apple Music app or Apple TV app.
From the Account menu in the menu bar, choose Account Settings.
Sign in to your Apple Account. Forgot the email address or phone number that you use with Apple Account?
Scroll down, then click Authorised Devices.

Click De-authorise All. If you don't see this option, then this is your only authorised computer.
Use the Apple Music or Apple TV app to authorise or deauthorise your computer, and to check your authorised computer count.
Open the Apple Music app or Apple TV app.
Click your name at the bottom of the sidebar. Or, click Sign-in and sign in to your Apple Account.
Click Authorise Machine or De-authorise Machine.

Sign in to your Apple Account. Forgot the email address or phone number that you use with Apple Account?
Click Authorise or Deauthorise.
Open the Apple Music app or Apple TV app.
Click your name at the bottom of the sidebar. Or, click Sign-in and sign in to your Apple Account.
Click View My Account. You may need to sign in to your Apple Account.
On the Account Settings page, look next to Computer Authorisations to see how many computers are authorised.

You have to deauthorise all of your computers, then authorise each computer that you have again. You can only deauthorise all computers once a year.
Open the Apple Music app or Apple TV app.
Click your name at the bottom of the sidebar. Or, click Sign-in and sign in to your Apple Account.
Click View My Account. You may need to sign in to your Apple Account.
On the Account Settings page, look next to Computer Authorisations, then click De-authorise All. If you don't see this option, then this is your only authorised computer.
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