Everything else is already in your Mac in the form of macOS Recovery, a special mode you can boot into.Ī secure internet connection just means your Wi-Fi needs to be protected by a WEP or WPA password, which most people’s home Wi-Fi networks are.Īs for how long it will take, that depends on a variety of factors but could be anywhere from 30 minutes to several hours, and you won’t be able to use your Mac during this time. To reinstall macOS, all you need is a secure internet connection and a fair bit of time. Follow our guide on how to wipe a Mac to sell it for detailed instructions, though we’ll also point out what to do in this guide as well. If you need to erase all the data on your Mac in order to give it away or sell it, you need to use Disk Utility to erase your hard drive before reinstalling macOS. However, it’s still a fairly major procedure to put your Mac through so we strongly suggest you back up your Mac before reinstalling macOS. That means your photos, music, documents, emails, and everything else should still be in place after reinstalling macOS. There’s no guarantee, but reinstalling macOS shouldn’t delete any content from your Mac. However, we’ll also show you how to reinstall the original version of macOS that came with your Mac or how to update to the latest compatible version as well. Typically, when reinstalling macOS doesn’t change the version of macOS running on your Mac it just installs that version again from scratch. This is an excellent way to fix software bugs as the errors that caused those bugs get rewritten with clean code in the process. Reinstalling macOS rewrites every line of code for the operating system on your Mac. How To Install macOS or OS X on a New Hard Drive for Your Mac.How To Factory Reset a MacBook Air or Other Mac With macOS.How To Fully Wipe Mac Hard Drive When Selling It.We’ll show you exactly what you need to do below.

That means you don’t need to be a computer whiz to get the job done. It’s incredibly easy to reinstall macOS thanks to the macOS Recovery partition Apple includes in its Macs.

You may also need to reinstall macOS if you’re prepping to sell or give away your Mac. You may need to reinstall macOS-the operating system on your Mac-if you’re experiencing software problems on your computer.

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