Accidentally Erased Hard Drive in Disk Utility? It’s Recoverable

Have you accidentally erased a hard drive using Disk Utility on Mac and are wondering if you can recover it? You’re not the only one! Every day, thousands of users around the world search for solutions that would let them recover an erased hard drive on Mac, but only a few find what they’re looking for.

Why? Because there’s a lot of misinformation online when it comes to data recovery solutions for Mac. The goal of this article is to help Mac users recover erased data in the quickest and most cost-effective manner possible, which is why we describe two different solutions, each suitable for a slightly different data loss scenario.

Does Disk Utility Erase Everything on the Hard Drive?

“Being the idiot that I am, I accidentally wiped an external drive (Seagate Backup Plus Slim 1.5 TB) using Disk Utility in OSX. Long story short, I wanted to move some old movies I had in a smaller drive to a bigger drive that was empty. I wanted to wipe the bigger drive completely, so I utilized the disk utility erase feature,” writes u/Jeffooie on Reddit.”

Sadly, posts like this one are far from rare. In fact, you’re guaranteed to come across at least one or two almost every day if you frequent popular Mac forums. But even though erasing the wrong internal or external hard drive seems like a pretty clear-cut problem to tackle, the truth is that some erased hard drives can be recovered using hard drive recovery software, while others can only be restored from a backup. 

Even though Disk Utility always erases everything on the hard drive, it doesn’t always overwrite the erased data, making their recovery impossible. It all depends on the security options. These options specify how to erase the selected drive to prevent hard drive recovery software from recovering it.

As a Mac user, you can choose between the following security options:

• Fastest: This option does not securely erase the files on the drive. A hard drive recovery software may be able to recover the files.
• Fast: This option writes a pass of random data and then a single pass of zeros over the entire drive.
• Secure: This option is a DOE-compliant 3-pass secure erase, and it writes two passes of random data followed by a single pass of known data over the entire drive.
• Most Secure: This option meets the US Department of Defense 5220-22 M standard for security erasing magnetic media because it writes over the data 7 times.

The good news is that the fastest security option is selected by default. So, if you haven’t changed the security options before erasing your HDD or SSD, you should be able to recover data from it using data recovery software for Mac.

What If You Can’t Boot the Mac After Deleting the Startup Disk

A pretty common problem that many users experience after deleting the startup disk on their Macs is not being able to boot their computers. If that’s what you’re experiencing, don’t worry, there is a way out of this scary situation.

So what should you do if your Mac won’t start after deleting its startup disk? The best solution is to boot your computer in Recovery Mode and either restore the disk from there or use a Time Machine backup to fix the issue. Check out Method #3 and Method #4 for more information.

How to Recover Erased Hard Drive / Startup Disk on Mac

It takes only one click to mistakenly erase your Mac’s startup disk. But luckily, there are data recovery methods for any situation.

Method 1: Recover an Erased Mac Hard Drive with Data Recovery Software

Assuming that you’ve accidentally erased your Macintosh HDD using the fastest erase option, you can attempt to recover lost data using data recovery software like Disk Drill.

Step 1. Download and Install Disk Drill for Mac

To get started, download Disk Drill for Mac and install it on a suitable storage device, which is any storage device except for the erased one. For example, if you’ve accidentally erased an external hard drive, you can safely install Disk Drill on your Mac’s internal hard drive without risking overwriting the same files you’re trying to recover.

Step 2. Launch Disk Drill and Scan the Erased Hard Drive

Next, launch Disk Drill from the Applications folder and scan the erased hard drive. To do that, you simply need to click the Search for lost data button, and Disk Drill will automatically apply all available recovery algorithms in the optimal order.

Step 3. Recover Selected Files from your Hard Drive

Finally, go through the list of recoverable files and select each and every file you want to get back. If you want to recover all files found by Disk Drill, you can press Command-A on your keyboard to select all items. Then, click the Recover button again and tell Disk Drill where it should recover the selected files. Again, you need to recover them to a different hard drive to avoid overwriting.

Method 2: Restore an Erased Hard Drive Using Disk Utility

But what if you need to restore a hard drive that has been securely erased? In that case, even the best hard drive recovery software won’t help you. Your only option is to restore the erased hard drive from a backup, which you can do with the help of Disk Utility.

Follow these steps:

1. Open Disk Utility from Applications > Utilities.
2. Select the volume you want to restore in the sidebar.
3. Click the Restore button.
4. Choose the volume from which you want to restore the erased hard drive.
5. Click Restore and then click Done.

Method 3: Use Recovery Mode Option (for M1 Apple Silicone Mac and for Intel Mac)

If you can’t start your computer after deleting its startup disk, the best solution would be to boot it in Recovery Mode. After that, you will need to repartition the startup disk and reinstall your Mac’s operating system.

Depending on whether you have an M1-based Mac or one with an Intel processor, the instructions for using Recovery mode will slightly differ.

Instructions for Apple Silicone Macs

Here’s how to use Recovery mode to recover the startup disk on an M1-based Mac:

1. Boot into Recovery Mode. Head to the Apple menu, click Restart, and immediately press and hold the power button. Release when the Startup Options window appears.
2. Click Options > Continue.
3. Choose Disk Utility.
4. Select the needed drive in the sidebar and click the Partition button.
5. Choose 1 partition and click Apply.
6. From the top menu, click Disk Utility > Quit Disk Utility.
7. Choose Reinstall macOS from the Recovery mode window and follow the onscreen instructions to complete the process.

Instructions for Intel-Based Macs

Here’s how to use Recovery mode to recover the startup disk on an Intel-based Mac:

1. Boot into Recovery Mode. Open the Apple menu and click Restart. Right after that, press and hold Command + R keys. Release the keys when the Apple logo appears on your screen.
2. Choose your user account and enter your password if prompted. Click Continue.
3. From the Recovery Mode menu, click Disk Utility and then the Continue button.
4. Choose the needed drive on the left side and click the Partition button.
5. Choose 1 partition and click Apply.
6. From the top menu, click Disk Utility > Quit Disk Utility.
7. Choose Reinstall macOS from the Recovery mode window and follow the onscreen instructions to complete the process.

Method 4: Restore Backup from Time Machine Drive

If you used Time Machine to back up your Mac, then you can easily recover your whole startup disk or hard drive with this tool. So plug in the drive containing your Mac’s recent backup version and follow these steps:

1. Restart your Mac. Head to the Apple menu and click Restart.
2. Boot into Recovery Mode. If you have an M1-based Mac, then press and hold the power button until the Apple logo appears on your screen. Or, if your Mac is an Intel-based one, press and hold the Command + R keys instead.
3. Choose your user account and enter your password if prompted.
4. When the macOS Utilities window appears, click Restore From Time Machine Backup.
5. Click Continue.
6. Choose the disk containing your backup and click Continue to confirm.
7. Select the needed backup version and click Continue to move further.
8. Choose the startup disk or the needed hard drive as the destination disk and click Restore.

You’ll get notified when the process is finished. As soon as that happens, restart your Mac and enjoy.

If you want to recover only specific files or folders from your Time Machine backup, then you can absolutely do so. Follow these steps to recover only the chosen data to your Mac:

1. Connect the drive containing your Mac’s recent backup.
2. Click the Time Machine icon in the menu bar.
3. Choose Enter Time Machine.
4. Select the needed backup version. Press and hold Command while clicking the files or folders you wish to recover.
5. When ready, click Restore.

Conclusion

A crisis can be averted even if you’ve mistakenly deleted your Mac’s startup disk. Luckily, there are a few ways out of this unfortunate event. Even in the worst-case scenarios, if you act quickly, it will be possible to successfully recover data from a deleted startup disk on your Mac.

Read also

How to Recover Data from Mac Hard Drive to PC

Hard Drive Recovery Software on Mac

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