How to Reinstall Mac OS: Easy Guides to Reinstall Mac OS to X Lion

How to Reinstall Mac OS: Easy Guides to Reinstall Mac OS to X Lion - Photo by Owner
SHARE - Most Windows users reinstall their operating system in various ways but it is not a common thing for Mac users. Whether you have major problems and want to start fresh, or planning to sell your Mac and need to reset, reinstall macOS is needed. This article will guide you how to reinstall Mac OS in simple and easy method.

What to Do Before Reinstalling Mac OS: Back up!

Let’s say, you have been using this computer for some time with personal data on it and wanting to know how to reinstall Mac OS without losing it all. Reinstalling macOS will erase everything on your system, so you'll need to back it up first. Before backing up, you may want to free up space by getting rid of old files you never use. The easiest way to back up is using Apple's built-in solution, Time Machine. If you only have a few files, you may want to sync your most important files to Google Drive or other cloud storage. Another alternative is to copy your vital folders to a USB flash drive. Whatever you choose to do, remember that this process will erase everything on your Mac.

Closing All Opened Application

Before continuing to the step of how to reinstall Mac OS, you should also take some times to quit the applications on your computer. Services like Adobe Creative Cloud limit the number of installs you can use, so you should head out to avoid wasting on non-existent systems.

Sign out of iTunes by opening it and choosing Account> Sign Out. You can log out of iMessage by opening Messages and choosing Messages> Preferences. Select your account on the left sidebar and select Sign Out. Finally, sign out of iCloud by visiting System Preferences> iCloud and selecting Sign Out.

After backing up your data, you can now head up to the main steps of how to reinstall Mac OS. These steps are for those who want to know how to install their Mac OS into X Lion. So, let’s take a look!

How to Reinstall Mac OS X Lion: Step-by-step How to Install Your Mac OS

How to Reinstall Mac OS X Lion: Step-by-step How to Install Your Mac OS - Photo by Owner

Boot into Recovery Mode - Photo by Owner

  • In the past, you could reinstall the OS via the DVD that shipped with your Mac. But since the new Mac doesn't have an optical drive, we'll use the built-in Recovery Mode to do it. This will work on any Mac running OS X 10.7 Lion or later.
  • Shut down your Mac. Hold down Cmd + R keys and turn it back on. Continue holding these buttons until you see the Apple logo. After a few moments, you'll see a macOS Utilities (or OS X Utilities) page with a few options.
  • If this doesn't work (maybe your computer is frozen on the Apple logo) you will need to start internet Recovery mode. This runs the recovery environment from the internet instead of a partition on your hard drive. Hold Cmd + Option + R at startup to access it. You will see a globe instead of the Apple logo.
  • Connect to a Wi-Fi network if you haven't already. Then wait a moment while your computer downloads the recovery environment. You need to select your language to enter the proper Recovery mode.
  • When using internet Recovery mode, the system may reinstall a different version of macOS than the one you are using. 

Erase Disk - Photo by Owner

  • Note that if you want to know how to reinstall Mac OS without losing any data, you'll need to skip this step and go to “Reinstall macOS” below.
  • In order to properly reinstall the OS, you will have to erase the disk first. To do this, choose Disk Utility from the menu.
  • Next, select your internal hard drive (usually labeled Macintosh HD) from the left sidebar. Switch to the Delete tab on the right side. Make sure the Format is set to Mac OS Extended. The Macintosh HD's default name is fine unless you prefer something else.
  • Click Delete and confirm the operation. Once done, you are ready to install the new macOS. Press Cmd + Q to exit Disk Utility.

Reinstall macOS - Photo by Owner

  • Back in the macOS Utilities menu, select Reinstall macOS (or Reinstall OS X). Click Continue to continue; Apple will verify your computer's eligibility to install the OS. You may see a request to enter your Apple ID as part of this process.
  • Accept the license agreement and click on your hard drive to select it for installation. Click Install to start the process. Depending on your computer specifications (and internet connection speed if using internet recovery), this will take some time.
  • Once you see the Welcome screen, your Mac returns to factory defaults. If you're selling or giving away your Mac, you can press Cmd + Q at this point. You will get a prompt to shut down your Mac; The next owner can continue with the arrangements later.
  • If you look after your Mac, you can go through the setup.

Set up your macOS - Photo by Owner

  • Select your region on the Welcome screen and click Continue.
  • Next, confirm your keyboard layout and hit Continue again. You will then need to be connected to the wireless network (you can skip this for now if needed).
  • Then, you will see the Transfer Information to This Mac screen. Here you can choose From Mac, Time Machine backup, or startup disk to import the data you created earlier. Select Don't transfer any information now to skip this; You can go through the process later.
  • Your Mac will then ask you to sign in with your Apple ID. Enter your credentials here to sign in, or select Create a new Apple ID if you don't have an account. If you want to use a local account, select Don't sign in. However, this will prevent you from using the App Store, FaceTime, and the like.
  • Accept the terms and conditions, then create your computer account if you are not signed in with an Apple ID. From here, give your computer some time to set up, and you will be greeted with your desktop. These steps of how to reinstall Mac OS are now completed and you can start using your Mac again with a new fresh.

Tips: Update macOS (if applicable)

  • You should check for macOS updates at this point. Go to the Apple Menu at the top left and click Software Update to open the App Store.
  • You'll see any updates available for the current version of macOS on the Updates tab, but you should also check on the Featured tab (or search for macOS) for the latest version of macOS available. Click Get and walk through the steps to initiate the update.
  • Depending on the age of your Mac, you might not be able to update to the latest version. 

These steps of how to reinstall Mac OS will work successfully if you’re following each of them. If you’re facing trouble in reinstalling, you should check it again as described on the steps above. Good luck!


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