Summary: This page is about how to reinstall macOS in macOS Recovery mode. Based on if you want to keep the original data on the startup disk, you can either choose to clean reinstall macOS or to reinstall macOS without data loss.
Reinstalling macOS gives your Mac a fresh start especially when you are frequently bothered by some issues, such as Mac not turning on, Mac hanging on the beach ball, apps frozen on your Mac, slow performance, or pink screen on Mac. Most of the time, such issue results from some system-level problems, while reinstalling macOS can easily save your life.
A clean install, in a nutshell, is a way of installing an operating system update that also overwrites your existing system and its data. To break it down, that means you’ll get rid of all of your files, documents, photos, apps, and other system data when you perform a clean install. In this guide we'll be going through how to install macOS Catalina step by step. Not all Macs can run Catalina, so you must check if yours is eligible. Luckily, Catalina's hardware requirements are the same as Mojave, so if your Mac is already running Mojave, then you can Catalina without any issues.
After that, you click on Power on this Virtual machine. At the first step, the VM will install macOS Catalina necessary files. It will take up to 20 minutes to complete the installation process. Installing macOS Catalina. After the installation is completed click on “Restart”. Want to install MacOS Catalina on a Mac? This article will show you how you can install and update MacOS Catalina upgrade on any compatible Mac. It’s a fairly straight forward process, and by following the steps you should be running the latest and greatest MacOS Catalina 10.15 in short order. Use the mouse pointer or the arrow keys on your keyboard to select the disk called Install macOS Catalina in the drive list that appears on the screen. Once the USB drive has booted, select Disk.
• How to reinstall macOS on an M1 Mac?
How to reinstall macOS from macOS Recovery mode?
When you need to reinstall macOS on your Mac, macOS Recovery mode makes this process easy and quick. By the way, if you want to learn more about macOS Recovery mode, you can watch this video.
To reinstall macOS in macOS Recovery mode:
Step 1: Make sure your Mac is connected to a stable Internet within all the following steps.
Step 2: Identify it's an Intel or M1 Mac, and immediately do one of the followings.
- Press and hold Command + Option + R.This allows you to reinstall the latest version of macOS that is compatible with your Mac computer from the internet.
- Press and hold Shift + Command + Option + R. This option allows you to reinstall the macOS that came with your Mac, or the closest version still available.
- Press and hold Command + R. This allows you to reinstall the version of macOS stored on your built-in recovery disk, including any updates that you installed.
• How to Boot into & Use M1 Mac Recovery Mode
Step 3: Release these keys when you see an Apple logo, spinning globe, or the Utilities window.
Step 4: Enter the requested password if you are prompted to enter a firmware password or the administrator's login password.
• Recover/reset your forgotten Mac password
• Mac won't accept correct password, what to do?
Step 5: Decide if you want to clean install the system, or just reinstall macOS without losing your original data.
If you want to factory reset the Mac for selling or giveaway, or the startup disk becomes corrupted, you might want to erase the startup disk before reinstallation. This guarantees a fresh and clean installation as it wipes all your personal data on the disk.
• How to factory reset your Mac?
• How to reset your M1 Mac to factory settings?
If you only want to reinstall macOS because the original operating system is not working as you expect, you might want to keep your personal data intact. In case files are deleted or lost by accident during macOS reinstallation, you should have a backup of your data or getting files off first.
• How to get files off a MacBook that won't turn on?
Step 6: Either after erasing the startup disk or getting files off the Mac, you can then go back to macOS Utilities and choose Reinstall macOS. Check this post to find all macOS versions and know which one you are going to reinstall.
Step 7: Follow the on-screen instructions and choose a disk to reinstall the OS.
- If the internal startup disk is not showing up, or the installer says that it can't install macOS on your computer or volume, you might need to back up files and then erase your disk.
- If the installer asks you to choose Macintosh HD or Macintosh HD - Data when installing macOS Catalina, choose Macintosh HD.
Other ways to install macOS
Apart from reinstalling macOS from macOS Recovery mode, you have other options according to your situations.
- Get released macOS versions or updates by App Store or Software Update preferences.
- Get macOS beta (such as macOS Monterey that might be buggy now) through Apple’s developer website.
Install Catalina Amd
Whatever your situation of reinstalling macOS is, you should always retrieve your data from the Mac before any further movement. After all, you can't tell if you want it back or not in the future.
After months of beta testing, Apple has rolled out macOS 10.15 Catalina to public users. You can download and install macOS Catalina if you have a compatible Mac. The macOS Catalina brings tons of new features such as the Apple Arcade, Screen Time, Voice Control, Sidecar, and Find My app. It has also replaced iTunes with three independent apps – Apple Music, Apple Podcasts, and Apple TV.
Is your Mac compatible with macOS Catalina?
Here’s the list of Mac devices compatible with the new software update:
- MacBook (Early 2015 or later)
- MacBook Air (Mid 2012 or later)
- MacBook Pro (Mid 2012 or later)
- Mac mini (Late 2012 or later)
- iMac (Late 2012 or later)
- iMac Pro (2017)
- Mac Pro (Late 2013 or later)
Install Catalina On External Drive
How to clean install the new software update
Upgrading to macOS 10.15 Catalina is pretty simple. Tap on the Apple icon in the top-left corner of the screen, then go to System Preferences > Software Update to download it. Alternatively, you can download it directly from the Mac App Store.
But sometimes upgrading macOS from the previous version to the latest one is not the best way. You might want to clean install macOS Catalina to give your Mac a fresh start without any issues from the previous installation. Here’s how to clean install macOS Catalina from USB drive:
Steps to install
- Take a full backup of all your important data. Save it to the cloud or an external drive
- You have to create a bootable USB drive. Here’s how you can create it. Make sure the USB drive is at least 8GB in size, and nothing else is stored on it
- Download the macOS Catalina installation file using this link
- Turn off the Mac and then insert the bootable USB drive
- Now turn the Mac back on while holding the Option key
- It will take you to the boot menu where you can select the USB drive. If your Mac has the T2 security chip, you have to first enable booting via external drives from macOS Recovery
- After a while, you’ll see the macOS Utilities menu on the screen. Select Disk Utility and then Continue
- Check to make sure you’ve selected the main drive of your Mac. Also ensure that the format is set as APFS or Mac OS Extended
- Now click Erase to wipe out the drive
- Once the drive has been erased, select Install macOS and then Continue. Just follow the on-screen prompts to clean install macOS Catalina
Install Catalina On Older Mac
Once you’ve successfully installed the new software, you can transfer all your data back from the cloud or external storage drive to the Mac. Also, head over to the Mac App Store and re-install all the apps you want.