How to do a clean install of macOS SierraFeel like you need a fresh start with macOS Sierra? Do a clean install!
Downloading and installing a new OS gives you the opportunity to do some major house cleaning if you so desire. If you feel like you'd like a fresh start with macOS Sierra, you can always opt to do a clean install: Just follow the steps below, even if you've already installed macOS Sierra.
Make sure you understand the difference between a clean install and a standard install before you get started.
Step 1: Back up your Mac
Step 2: Create a bootable drive of macOS Sierra
Step 3: Erase macOS Sierra
Step 4: Install a new copy of macOS Sierra
Note: If you are reading this article on the Mac you want to perform the clean install with, switch to another device or print this page before continuing so you can read along as you go.
Step 1: Back up your Mac
This process will erase whichever OS you're currently using from your hard drive entirely. That means any files, programs, or documents you have will be deleted....
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How to do a clean install of macOS Sierra