[macOS Guide] | How to Reinstall macOS

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Are you wondering how to reinstall macOS on iMac/MacBook Pro/Air without USB or CD? Installing macOS on Mac devices successfully in one go is like passing the toughest exam ever.

However, if you run into any issues, you might get frustrated, and the task of installing macOS can become challenging. There are several ways to install macOS on a Mac. We have chosen two methods of reinstalling through the App Store that will allow us to download and install the latest version of Mac OS. Follow the instructions in this article to reinstall macOS on your Mac device in under an hour.

Reinstall macOS from Recovery

Has your Mac been acting up lately? It might be time to install a new operating system. Using Recovery Mode on your Mac is an easy way to restore your macOS or install a fresh copy. First, let's look at how to enter Recovery Mode to get the latest version of macOS:

Step 1: Restart your Mac. You can do this by pressing the power button or selecting "Restart" from the Apple icon in the top-left corner of the screen.

Step 2: As your Mac restarts, press and hold the Command-R keys. Hold them down until you see the Apple logo, then release.

You are now in recovery mode. To start installation, please proceed as follows:

Step 1: In the Utilities window in macOS Recovery, choose Reinstall macOS, then click Continue and follow the onscreen instructions.

Step 2. Click Agree. Then, select your hard drive. Click Install to begin erasing and reinstalling macOS.

How to Install an Older Version of macOS

If your Mac is running poorly with a newer version of macOS, you may want to downgrade to an older system version. However, not all versions of Mac OS X are compatible with every device. Apple's M1 chip doesn't allow you to use earlier versions of Big Sur on your Mac. As a general rule, a Mac will only run the operating system it came with or any later versions.

Step 1: Make sure your Mac can run the version of macOS or Mac OS X that you want to install.

Step 2 Download the installer for the version of Mac OS X or macOS that you want to install.

Step 3: Once you've downloaded the installer, run it, and your Mac will be updated (or downgraded, as it were).

Important: If your Mac is using a new version of macOS, you can't keep an older version. Before installing an earlier version of macOS or Mac OS X, you need to erase all data from your Mac.

How to Avoid Data Loss When Upgrading or Reinstalling macOS

When your Mac is running poorly or experiencing hardware issues, you may need to update or reinstall macOS. Many people worry that reinstalling the operating system will erase all their data.

During the reinstall, you can use a data recovery program or a backup of your Mac's content to ensure that your data is safe. You can back up your data in one of two ways:

1. Time Machine Backup

Using Mac's built-in backup tool, Time Machine, ensures that all your data – applications, music, photos, emails, and documents – are backed up. If you accidentally delete or lose data, you can recover it from the backup.

Step 1. Connect an external storage device (like a USB).

Step 2. Open Time Machine from the menu bar, or choose Apple menu > System Preferences > Time Machine.

Step 3: Select the backup disk!

Step 4: Select the disk, then click “Use Disk.” Time Machine will now begin making automatic backups in the background with no further setup required on your part.

How to Retrieve Files After Factory Reset on Mac

On this page, you'll find practical solutions to undo deletion and recover files after a factory reset on Mac, along with an extra guide on how to reset your MacBook Pro without losing data.

2. Tool: Data Recovery Wizard

If you had backed up your Mac data before reinstalling, you could restore it from Time Machine, an external hard drive, or any other location. If you didn't create any backups for your Mac, you will need to use a Data Recovery Wizard tool to get your data back. The software enables free Mac data recovery in case of macOS reinstallation.

There are many data recovery tools. The best Mac data recovery tool is Data Recovery Wizard. It can quickly recover all lost data. It can also restore your office files, music, movies, and emails.

If you encounter data loss after reinstalling macOS, you can follow these steps to recover lost data using the Data Recovery for Mac tool.

Step 1: Select the scan location

Run the Mac Data Recovery Wizard, select the hard drive, SSD, SD card, USB flash drive, or TF card from which you lost data. Click "Find Lost Files" to start scanning.

Note: Before you proceed with data recovery, it's recommended that you click “Disk Backup” from the left sidebar and create a backup of your Mac to prevent further data loss. After the backup, the software can recover data from the Mac backup, and your computer will be free to write new data.

Step 2. Filter out Lost Mac Data

The software will automatically scan for lost data on your MacBook or iMac. After the scan, you can filter the required data using the "Type" and "Path" buttons.

Step 3: Recover Lost Data or Files

Preview the files by double-clicking them. Then, click “Recover” to restore the lost data to another location.

"People are also asking,"

How do I erase and reinstall my iMac?

To ensure a clean reinstall, you must first erase the hard drive using Disk Utility. Follow these simple steps:

Step 1: Launch Disk Utility.

Step 2: Depending on how you started Recovery, Disk Utility might open automatically. If it doesn't, choose Utilities from the menu bar and then Disk Utility.

Step 3: Look through the list of drives and click “Erase” next to your main drive.

After erasing, you can reinstall macOS

Step 1: If you have a recovery partition available, select "Reinstall macOS." The installer will start. Click "Continue" to install to the USB drive.

Step 2: The utility will prompt you to select a disk. Choose the one labeled "Macintosh HD."

Step 3: The macOS installer starts.

2. Does reinstalling macOS delete everything?

No, it will not. Reinstalling MacOS will not delete anything else. You can reinstall Mac OS X over the existing operating system. By using Internet Recovery, you can reinstall macOS without losing any data. Click "Restart" on your desktop. Hold down Command + R until you see the Apple logo. Then, select "Reinstall macOS Big Sur" from the Utilities menu.

How can I reinstall macOS without Internet?

Using Command+R to restart your Mac will reinstall the current version of macOS that you have. If you already have 12.1, you will need an internet connection to install it. When you use Command+R to restart, it installs a fresh version of the operating system.

Conclusions

On a Mac, you can usually reinstall macOS in Recovery mode. As a precaution, we've provided instructions on how to reinstall macOS on an iMac/MacBook Pro/Air. However, it's essential to back up your data before reinstalling macOS. If you lose your data, the Data Recovery Wizard can help you restore it. Once the reinstallation is done, enjoy your refreshed Mac!