7 feasible solutions to fix Macintosh HD not mounted/showing in Disk Utility

By Katrina | Posted to Mac Data Recovery, updated on May 26th, 2020 |

Summary: Mac HD not mounted? Macintosh HD not showing in Disk Utility? Don't worry. This article will show you 7 efficient solutions to fix Macintosh HD not mounted/showing in Disk Utility in macOS Catalina/Mojave/High Sierra issue without losing data.

Mounting a drive means to make the drive available for the operating system to read and write. If the Macintosh HD not mounted in Disk Utility, it means all data on the Mac HD becomes inaccessible. What's worse, your Mac won't turn on at all just like this user:

Help, my 2011 iMac just randomly stopped working this morning. I turned it on, it took about 3 minutes to get to halfway then it shuts off. I went to macOS Recovery mode and find Macintosh HD was not mounted as it was greyed out in Disk Utility. I don't know how to. Would I need to erase my Macintosh HD or is it possible to recover files from an unmounted, unrepairable drive?

So, to better fix the knotty issue of Macintosh HD not mounted, read through this guide and find a solution for yourself.

Table of contents
1. What is the Macintosh HD?
2. Why does Macintosh HD not mounted?
3. How to rescue data when Macintosh HD not mounted?
4. How to fix Macintosh HD not mounted?
5. How to fix Macintosh HD not showing in Disk Utility?

What is the Macintosh HD?

The Macinotsh HD is a volume of the Mac startup disk, and it holds the operating system and system files. In the latest macOS, the Macintosh HD volume is read-only and locked. So, users have no access to this volume.

In macOS Catalina, except for the Macintosh HD, another volume called Macintosh HD - Data is introduced for saving your personal files and data separately. In the Finder, both volumes appear as Macintosh HD.

However, for some reason, the Macintosh HD may be not mounting on Mac as you expect. As a result, the Mac gets stuck when loading boot information.

Why does Macintosh HD not mounted?

In fact, Macintosh HD not mounted problem is quite common in macOS Catalina, Mojave, High Sierra and any other operating system. In some older operating system, it could be disk0s2 not mounted in Disk Utility.

Macintosh HD not mounted Mac

But have you ever thought, why is the Macintosh HD not mounted on Mac like before?

In the following part, we will unveil 5 primary reasons why this might happen:

  • File system damage. File system is responsible for how data is organized and stored in a drive. If the file system of the Macintosh HD is corrupted, the master file table will be impacted in a direct manner so the Mac won't mount Macintosh HD.
  • Virus attacks. Perhaps, your Mac system or the Macintosh HD is attacked by virus or malware, resulting in data corruption. Then your Mac won't mount the Macintosh HD, either.
  • Catalog file corruption. Catalog files contains the record files of partitioned volumes. So if any catalog file becomes corrupt, the Mac won't be able to get the boot volume size location, description of volume content and other volume information. So, no startup disk will be recognized by your Mac.
  • Disk Utility failures The Macintosh HD not mounted issue may be caused by Disk Utility faults, too.
  • System malfunctions. System malfunctions include machine malfunctions and operating system errors. If the Mac operating system crashes, it cannot mount any drive but shows the prohibitory symbol at Mac startup.
  • Hardware issue. Hardware issue can also cause Macintosh HD not mounted issue.

Now, you have a brief idea of the causes for Macintosh HD not mounted issue. The next thing you should worry about is your files on the Mac HD as you can't access them right now.

How to recover data when Macintosh HD not mounted?

Pro tips: Before fixing the Macintosh HD not mounted issue, please stop using the Mac computer. That's because, your any further operation on the Mac computer may write new data to the unmounted Macintosh HD and overwrite the original data.

So, to prevent unnecessary data loss, make sure you have a backup copy of the Macintosh HD before troubleshooting the Macintosh HD not mounting errors. Without backups? You can get files off the Mac hard drive when Mac is not turning on or use Target Disk Mode to get files off.

Method 1: Recover data from unmounted Macintosh HD with iBoysoft Data Recovery for Mac

To recover data from unmounted Macintosh HD, you need to run iBoysoft Data Recovery in macOS recovery mode.

iBoysoft Data Recovery for Mac is free Mac data recovery software which helps you recover lost data from the unmounted Macintosh HD. Except for recovering data from unmounted Mac internal hard drive, it can also recover lost data from USB flash drives, external hard drives, and SD cards and more. It can recover deleted files on Mac, and recover lost data from formatted, unreadable, corrupted drives, etc.

iBoysoft Data Recovery for Mac is fully compatible with macOS Catalina 10.15/Mojave 10.14/High Sierra 10.13/10.12 and OS X 10.11/10.10/10.9/10.8/10.7.

Method 2: Use Target Disk Mode

Target Disk Mode is a boot mode which allows you to browse and transfer files from a Mac internal hard drive without booting macOS.

Target Disk Mode can be used for troubleshooting the internal hard drive not showing up on Mac.

How to fix Macintosh HD not mounted in Disk Utility?

After recovering data from the unmounted Macintosh HD, you can follow the solutions to fix the "Macintosh HD not mounted" issue.

Solution 1: Restart your Mac computer

If you see a blinking folder on Mac at startup or you press Option but find no Macintosh HD in startup disk, the first and foremost solution is to shut down your Mac computer and start it up again. Simply holding down the on/off key until the computer turns off, waiting a few minutes, and then turning it back on. Sometimes when you turn it back on, everything returns to normal.

Solution 2: Repair the unmounted Macintosh HD in macOS Recovery Mode

If the Macintosh HD is not mounted in Disk Utility normally, you can try to fix it with Disk Utility's First Aid in macOS Recovery mode.

Solution 3: Fix Macintosh HD not mounted by Terminal

If Disk Utility cannot repair the disk, you can then try to fix it with Terminal.

Step 1: Boot your Mac into macOS Recovery mode.

Step 2: Click Utilities from the menu bar and select Terminal from the drop-down list.

Step 2: Enter diskutil list. This will list out the available volumes.

diskutil list

Step 3: Check the volume identifier from the table that appears. (For example disk 2s)

Step 4: Enter diskutil repairVolume/disk 2s. (Replace disk 2s with the volume identifier of your Macintosh HD)

diskutil repairVolume/disk 2s

Solution 4: Run FSCK command in Single User Mode

FSCK is a command-line tool to check the consistency of a hard drive and repair disk errors. If the solutions above are unable to fix Macintosh HD or the Mac internal hard drive not mounted issue, you can have a try.

Step 1: Restart your Mac and, before the Apple logo appears, hold down Command and S keys. This will boot your Mac into Single User Mode.

Step 2: Type in:

/sbin/fsck -fy

Step 3: If you see "File system was modified", then re-type in the command again until you see "The volume [name] appears to be OK".

Use FSCK command in Single User Mode

Step 4: Type in the command to restart your Mac:

reboot

Solution 5: Try Safe Mode

When trying to boot into Safe Mode, macOS will scan and repair any errors it finds on the disk. To boot into Safe Mode, you need to shut the Mac down and start it up while holding down Shift. Release the Shift key when you see the login window. Should your computer boot properly, try restarting and booting as normal.

Solution 6: Reset NVRAM on your Mac

NVRAM is a small amount of memory used to store certain settings for quick access on Mac. The corrupted NVRAM can cause Mac glitches or even prevent macOS from starting. Thereby if your Mac computer won't boot properly because the Macintosh HD is not mounted, you can attempt to reset the NVRAM. Reboot your Mac and hold down the Command + Option + P + R key buttons. After resetting, you can retry to mount the Macintosh HD on Mac.

Solution 7: Erase the Macintosh HD and reinstall macOS

If you failed to repair the unmounted Macintosh HD, and your Mac still cannot recognize the Macintosh HD, the final chance is to factory reset the Mac - format the Macintosh HD and reinstall macOS on it. But as you know, reformatting will erase all the data stored on the Macintosh HD. Please make sure you have recovered data with iBoysoft Data Recovery for Mac as above.

Step 1: Boot your Mac to macOS Recovery Mode.

Step 2: Select Disk Utility from the macOS Utilities menu.

Step 3: Select the unmounted Macintosh HD from the side bar.

Step 4: Click Erase from the top.

Step 5: Setup the required information (i.e. Name, Scheme, Format, etc.) to reformat the disk and click Done when finished.

Step 6: Go back to macOS Utilities screen and select Reinstall macOS.

What to keep in mind: Once you encountered the Macintosh HD not mounted Catalina/Mojave/High Sierra/Disk Utility error, the first thing you should do is to save your data on the Macintosh HD. Without regular backups, a data recovery program like iBoysoft Data Recovery for Mac will help you recover lost data from the unmounted Mac hard drive. Then, try to fix the Macintosh HD not mounted issue.

How to fix Macintosh HD not showing in Disk Utility?

If Macintosh HD doesn't appear in Disk Utility, it means your Mac has a hardware issue. If it is that case, please send your Mac to Apple store and ask a specialist to repair it.

Final thoughts

It's so frustrating that Macintosh HD greyed out in Disk Utility in macOS Recovery mode, especially when you have important data stored on the Mac. But the good news is that quite a few feasible solutions are available to fix this issue. Before that, if you care about data on the Macintosh HD, you should recover lost data from the unmounted Macintosh HD with iBoysoft Data Recovery for Mac. Download and install this free Mac data recovery software, you won't be bothered by any data loss scenarios.

Which solution helps you the most? Do you have any other solutions to fix Macintosh HD not mounted issue or have any question? Please don't hesitate to email us.