It will be saved in the Applications folder. Your Mac will now download the installer file.

You will get a message warning you that macOS 10.13 is already installed on the computer. If you have purchased or downloaded it before, you can look for it in your Purchased tab. Here’s how to get installation files if you are installing macOS High Sierra. You can get these from the Mac App Store. The next thing you need is the macOS installation files. It will be best to use a Flash memory stick, but if you’re using a portable hard drive, we recommend USB 3.0, USB Type C, or Firewire. Even though the installation file size of High Sierra is 4.8GB, Apple recommends that you have 12GB storage available on your flash drive to allow for a more secure and stable installation. You need one with at least 12GB of free storage. There are two primary items you need to create a bootable USB to reinstall macOS. What You’ll Need to Create a Bootable MacOS Installer In this article, we’ll show you how to make bootable USB so you can install macOS or an older version of it in case you can’t or don’t want to reinstall using recovery mode and other methods. Aside from using recovery mode to reinstall macOS, you can also choose to make Mac boot from USB. Similarly, there are also various ways to reinstall macOS. It’s also possible that you’re the recipient of that old Mac. Maybe you need it to reinstall macOS to fix a problem in your system or perhaps you’re planning to sell or hand down your old Mac to a new owner. There are various reasons why you would need a macOS installer.

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