How to Reinstall macOS Catalina

This article explains how to reinstall macOS Catalina on a Mac. Apple makes it easy. All you need is an internet connection, and you’re set.

How to Fresh Install macOS Catalina 

It's a good idea to back up any important files you have prior to reinstalling. You need a reliable internet connection because the Mac downloads the files it needs from the internet. Apple built a recovery mode into macOS for times when you need to reinstall an operating system.

1. Click the Apple logo and select Restart.

2. Click Restart.

3. As soon as the computer starts to shut down, hold down Command+R. Continue holding these keys past the black screen and/or music you hear when the computer boots up (depending on how old the Mac is) until you see Recovery Mode. Then release the keys.

4. You may be prompted to select a user you know the password for. Click the user and click Next.

5. Enter the password for the user you selected.

6. Click Reinstall MacOS > Continue.

7. Click Continue.

8. Click Agree to agree to the software license agreement.

9. Select the disk where you want to install the operating system. In some cases, you may need to unlock the drive. Click Install or Unlock. 

10. If you had to click "Unlock," enter the password for an administrator on the computer. Usually, it is the same password as the one you entered in Step 4.

11. If you had to unlock, now click Install.

12. The computer takes a while to download and install the operating system. Expect to wait 15 to 25 minutes, depending on the speed of your internet connection and computer. When the installation is complete, your computer restarts. 

    Any slowdowns or other issues you noticed should be cleared up. If not, think about completely reinstalling everything. Fortunately, there are ways to do that, too.

After Reinstalling macOS Catalina

After you complete the reinstall, check for updates to make sure you have all the latest software. 

1. Click the Apple logo and select System Preferences in the drop-down menu.

2. Click Software Update.

3. Your Mac checks to make sure you have the latest software installed. If so, it lets you know. Otherwise, it prompts you to install any updates that are available.