It's time to sell your old Mac so you can buy a new one - here's how!How do I clear my Mac so I can sell it? You have to reformat your hard drive and reinstall a clean version of the operating system.
Prepping your Mac for Sale
Back up
Sign out
Unpair
Erase
Reinstall macOS
Troubleshooting
So, you're thinking about buying (or already bought) a new Mac, and you're considering what to do with your old one. You could hand it over to a friend or family member, keep it as a just-in-case backup (you know, for testing betas!), or you could sell it. If you know it's leaving your hands, you must reset the Mac before selling it or giving it away. Not only will this protect your information, but it's also harder for the new owner to use or access some of Mac's features if your digital prints are all over it.
The first thing you should do before hitting the streets to sell your old Mac is clear it of any personal data. You don't want to accidentally sell your computer to a stranger when you are still logged into iCloud.
The next step is to reinstall ...
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It's time to sell your old Mac so you can buy a new one - here's how!