Need to start fresh with your Mac? Looking to install an older or upgraded version of macOS but struggling to find the best way to do it?

There’s nothing to shy off. In fact, most Mac owners need to learn how to reinstall macOS because it’s uncommon among them, unlike Windows users, who often perform reinstallation on their systems.

In this article, we will discuss situations when you need macOS reinstall and how to do it right.

But before we jump to the ‘How-to’ part, let’s see when does it actually make sense to reinstall your macOS?

Why would you need to Reinstall macOS?

Why-would-you-need-to-Reinstall-macOS

MacOS is a subtle operating system that is self-sufficient in itself. However, being a work of AI, you never know when things might go upside-down.

When they do, Apple offers plenty of ways to troubleshoot your problematic Mac. However, if the problem still exists, reinstalling macOS can be an ideal solution.

Let’s look at some cases where reinstalling your macOS is worth the effort.

#1. When Your System is Messed Up

Since you have been working on your system for a while, you will immediately sense if it’s acting weird.

Like error messages pop up frequently, the software lags way too often, or some usability issues affect your everyday work – anything that makes you feel like your system is not functioning normally. 

Generally, no one expects to encounter such issues while using an Apple product. And we agree these system errors are rare, very rare, but they do occur.

They are more likely to occur with savvy coders or tech enthusiasts who regularly try out new software and make tweaks to system settings. 

As they say, curiosity has no boundaries. 👨🏻‍💻

So, if you ever feel you messed up with system settings, there’s nothing to panic about because reinstalling the macOS can be your way out.

#2. When Your System’s Running Slower Than Expected

Generally, some common factors such as over-storage or running an outdated macOS result in system slowdown. 🐌

But if your Mac is snail-paced even after keeping up to date with your system updates, it’s high time you try reinstalling your macOS. It gives a fresh start and will likely speed up your system’s performance. ⚡

However, make sure to create a copy or backup your files and data before initiating the reinstallation.

#3. When You’re Selling Your Mac

Of course, you won’t compromise your data when selling out your laptop. And you will figure out the best ways to wipe out everything from your Mac. But what if some confidential data remains undetected?

Perhaps you didn’t go for it the right way!

To ensure that everything is done and dusted, reinstalling your macOS can be an ideal option.

It’s a trial-and-tested method to wipe out your configuration from the root and prepare the Mac for the next person.

#4. When You Want to Downgrade Your System

Yes, people do it quite often, and here’s why.

You see, upgrading to a new version is always exciting and painless. But just sometimes, these upgrades can be overwhelming.

Perhaps the latest version has a thing that affects your workflow, or maybe it’s too heavy to run smoothly on your older machine.

In such cases, downgrading macOS is a viable option.

Now that we know why and when reinstalling macOS makes sense, you may ask how you actually get started with it.

Now we will cover all ways to reinstall macOS on mac.

Using a Bootable USB

using-a-bootable-usb

Using a bootable USB drive to install or update your macOS allows you to perform the process on multiple systems simultaneously without having to download an installer every time.

Besides, a bootable disk can be used for clean installation – format all files and apps that might have accumulated over time.

Let’s see how you can reinstall macOS using a bootable USB.

Step 1: Download macOS 

To create a bootable installer, you need two things:

  • A volume or USB drive with at least 16 GB of storage
  • A Mac that’s compatible with the OS version you are downloading

Acquiring a USB drive is something you can easily do. Just ensure you buy it from an authentic store and it’s not corrupted.

Now, to get the correct installer, download from a Mac that uses macOS Sierra 10.12.5 or later or El Capitan 10.11.6.

Remember: Always download the macOS from Apple’s official website and nowhere else.

downloading-macos

Once initiated, the macOS file will be automatically downloaded to your application folder with a default name as ‘macOS (version name).’

Step 2: Create Bootable USB Using the Terminal

Plug in the USB or other volume you’re using as a bootable installer to your system. Then open Terminal from the Utilities folder and paste the code below based on the macOS version you are dealing with.

sudo /Applications/Install\ macOS\ Monterey.app/Contents/Resources/createinstallmedia –volume /Volumes/MyVolume

For example, replace ‘Monterey’ with the macOS version you are installing and ‘Volume’ with the name of the USB or drive you are using as a bootable installer.

Once you are done editing the code, type or copy-paste it into the Terminal and press Return to run the command.

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Then, type your administrator password when prompted and press Return.

Here on, you will be asked if you wish to erase the volume (USB). 

To continue, press Y and then again press Return.

You can see a progress bar ‘Erasing disk’ indicating the percentage of volume erased. Wait for it to reach 100%.

After the volume is erased successfully, you may be prompted with an alert asking permission to access files on the removable USB. Click OK to allow the copy to proceed. 

Once done, the USB will have the same name as the OS version you downloaded, for example, macOS Monterey or macOS Catalina.

That’s it! You have successfully created a bootable installer. Now exit the Terminal and eject the USB.

Step 3: Use Bootable Installer

Now it’s time to use the bootable USB to reinstall macOS on your system. The process differs depending on whether you use an Apple Silicon or an Intel-based Mac. But no worries, we got you from here:

For Apple Silicon

Plug the bootable installer into the system you want to install macOS. Ensure that the system is connected to the internet and is compatible with the macOS version being installed.

Once you have made sure of these things, long-press the power button on your Mac until you see the Utilities window. Then, select the volume containing the OS from the given options and click on Continue.

For Intel-based Mac

The initial process for an Intel-based mac is similar to Apple Silicon, plugging the installer and checking for connectivity and compatibility.

Then, long-press the Option key until you see a list of volumes on the screen. Choose the volume with the bootable installer and press Return.

Recovery Mode

Another prolific way to reinstall your macOS is via its in-built recovery mode. Mac recovery mode is a specially designed feature that allows you to reboot the system even when your Mac can’t reboot automatically.

You can use this mode to reinstall OS, wipe a MacBook, factory reset the system, restore your data from Time Machine backup, and more. 

To begin with, turn on your Mac and long-press Command + R (for Intel Mac) or the power button (for Apple Silicon) until you see an Apple logo (or a spinning globe).

When prompted, enter the firmware password or administrative credentials. If everything goes as planned, the macOS Utilities window will pop up.

Now, if you wish to completely wipe your Mac before moving forward with reinstallation, click on Disk Utility

macos-utilities-menu
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If you’re running macOS Catalina or later versions, you need to erase two volumes, first the Macintosh HD- Data and then the Macintosh HD.

However, if you aren’t using the said versions, you can wipe the entire system data by solely deleting the Macintosh HD volume.

Once you have formatted the disk, press Command + Q to jump back to the macOS Utilities window, then press Reinstall macOS.

Note: If you don’t want to erase the disk, you can simply click on Reinstall macOS to get started with the process.

At this stage, you may be prompted to enter your Apple ID or your Mac password. It’s best to follow the on-screen instructions from here. 

The reinstallation process might take a while, so ensure you don’t put your Mac to sleep, turn it off, or even close the lid.

After the reinstallation is complete, you will see a login window. And you’re all set for a fresh start.

Mac Internet Recovery Mode

Mac-Internet-Recovery-Mode

Basically, this is an alternative if the Mac recovery mode doesn’t show up. Yes, it might happen that your Mac recovery mode gets corrupted, and here are a few ways to identify when it happens:

  • Your Mac didn’t boot into recovery mode after you press Command + R
  • A blank screen occurs after you try entering into the macOS Recovery
  • You receive the error code – 2003F on the screen

If you experience any of these incidents, your macOS recovery mode isn’t functioning.

But despite that, you can still use its Internet Recovery Mode to troubleshoot your problematic Mac.

Like recovery mode, this mode directly connects your system to Apple’s servers and offers you recovery utilities. All you need is reliable network connectivity.

Internet recovery mode only supports networks using WEP (Wi-Fi Equivalent Privacy) and WPA (Wi-Fi Protected Access) security. So make sure you have one of those lined up.

For M1 and M2 chip Macs, if the recovery mode isn’t working, the internet recovery automatically reboots the system.

But for older models of Mac, you need to enter the Internet Recovery Mode manually. 

Here’s how you can do it:

Step 1: Shut down your Mac

Step 2: Press the power button and immediately long-press Command + Option + R or Command + Shift+ Option + R until you see an icon or message on the screen

Step 3: Configure with a WEP/WPA-secured Wi-Fi connection

Step 4: Wait for the system to reboot itself

That’s it! 

The macOS recovery utilities window will automatically pop up. Then after, you can use the same process described in the above section to reinstall the OS.

Can You Reinstall Older Versions of macOS Using the Recovery Mode?

Yes, macOS recovery mode allows you to reinstall older or even upgrade to better versions of macOS. 

Besides, you can use several keyboard combinations to reinstall your desired OS, like:

  • Command + R: To reinstall the same OS that was installed on your system
  • Option + Command + R: To upgrade to the latest macOS that’s compatible with your Mac
  • Shift + Option + Command + R: To reinstall the default macOS or the closet version to it

However, it ultimately depends on whether your system is compatible with the version of macOS you are trying to install or not. 

Frequently Asked Questions

How to reinstall macOS from a USB

To reinstall macOS from a USB, follow the below steps:
1. Download your preferred macOS on an existing system
2. Create a bootable USB using Mac Terminal
3. Plug the bootable installer into the system you want to reinstall OS
4. Choose the volume or disk which has the OS files and press Return

How to reinstall macOS using Recovery Mode

Turn off your Mac, press and hold Command + R until you see a logo or a spinning globe on your screen and then release the buttons.
Wait for the macOS Utilities window to pop up, and then click on Reinstall macOS to start the reinstallation process.
Ensure that you don’t turn off, close the lid, or perform any action until the reinstallation process is complete to prevent complications.

Wrapping Up

If you’re an old Mac user, there will come a time when you will have no other option but to reinstall macOS on your desktop.

It can be due to the slow processing powers of the mac, to reset the mac in order to sell it, or can be because you might want to install an older OS version.

Whatever the reason, all the methods mentioned above will help you reinstall macOS safely and as efficiently as possible.

You may also explore some best disk cloning software for mac.