What computers are authorized?

Perhaps your initial inquiry should have addressed use of iPhone to determine

how to see what computers were authorized on your iTunes or iCloud accounts.

There -instead of Early MacBook 13-inch 2006~2010- could've been more helpful.

And there's the Apple Support App. [ You didn't mention the iPhone in original Q: ]

• Apple Support on the App Store - iTunes - Apple

Download Apple Support app for iOS. Enjoy it on your iPhone, iPad, and iPod touch.

..Otherwise the first reply was adequate: After all, you can 're-authorize' quite easily..

Good luck & happy trails! 🙂

Anytime you authorize a computer it stays authorized until you physically go in and un-authorize it from your account. Un-authroizing all isn't really going to do anything more then remove all from the list and then you can simply just authorize the ones that you want to have on it again. It's not possible to look up which ones you have authorized for security reasons and if you authorize a computer and later get rid of that system, then you need to make sure that you go in and un-authorize it before getting rid of it. You are allowed 5 systems to be authorized at a time and if you feel that you have some that you aren't using anymore (which is most likely what you would need a list of what is available) then you can un-authorize all and then authorize the ones you wish to keep. It's not going to remove any music or anything, it's simply not going to allow it to use that data until it is authorized again.