How to fix Macintosh HD partition not mounted error without data loss?

Posted by Molly to Mac Data Recovery on July 4th, 2018

This morning, I tried to boot my 2013 MacBookPro, it took about 3 minutes to get to halfway then it shuts off. I loaded recovery mode, but Macintosh HD was greyed out on the left side and when I tried to mount it nothing happened. Anyone knows why Macintosh HD partition can't be mounted? Is there another possibility to mount Macintosh HD partition or to access my data somehow?

Macintosh HD partition is usually the startup volume from which your Mac computer can boot up. If the Macintosh HD partition does not mounted, or the Macintosh HD partition icon greyed out in Disk Utility, you'll be unable to boot up your Mac as normal. Subsequently, you'll be unable to access the data stored on the Mac hard drive.

This article will show you how to fix the Macintosh HD partition not mounted error and help you recover data from the unmountable Mac hard drive.

How to fix Macintosh HD partition not mounted error?

Macintosh HD not mounted error could be due to various reasons, including file system damage, catalog files corruption, operating system crashes or virus attackes, etc. You can try out the solutions one by one to fix the Macintosh HD partition not mounted error.

Solution 1: Fix Macintosh HD partition not mounted error in Recovery Mode.

Step 1: Restart the computer and hold down the Command and R keys immediately when the Mac turn on. Release the keys until you see the Apple logo. This will boot the Mac into Recovery Mode.

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

Step 3: Select the unmounted Macintosh HD partition from the sidebar.

Step 4: Click First Aid on the top of Disk Utility window.

Step 5: Reboot the computer to check if the Macintosh HD partition is mounted.

Solution 2: Fix Macintosh HD partition not mounted error by reformatting.

If you failed to fix the unmounted Macintosh HD partition in Disk Utility, then you have to erase the Macintosh HD paritition and reinstall the macOS. This process will wipe out all the data stored on the Mac hard drive, so you'd better recover data from the unmounted Macintosh HD partition with iBoysoft Mac Data Recovery.

iBoysoft Mac Data Recovery is able to recover data from unmountable APFS boot volumes, recover data from corrupted boot drives, and recover data from startup drives on macOS High Sierra/Mojave/Sierra and 10.11/10.10/10.9/10.8/10.7.

Method 1: If you have only one unbootable Mac computer

If you have only one Mac computer, please directly run iBoysoft Mac Data Recovery bootable media from iBoysoft Server and recover lost data from the unmountable Macintosh HD partition.

Method 2: If you have two Mac computers

Step 1: Download iBoysoft Mac Data Recovery on another Mac computer.

Step 2: Install and launch iBoysoft Mac Data Recovery.

Step 3: Click iBoysoft Data Recovery on menu bar and then select "Create Boot Drive".

iBoysoft Data Recovery create bootable drive

Step 4: Insert a USB drive into your Mac computer.

iBoysoft Data Recovery create bootable drive

Step 5: Follow the wizard to create a bootable recovery drive.

iBoysoft Data Recovery create bootable drive

iBoysoft Data Recovery create bootable drive

Step 6: After that, please insert iBoysoft Mac Data Recovery bootable USB drive into the unbootable Mac computer, and then press the Power button and Option key (⌥) to start the computer up.

iBoysoft Data Recovery create bootable drive

Step 7: Select iBoysoft Mac Data Recovery from the boot options.

Step 8: Follow the wizard to scan for lost data on the unmounted Macintosh HD partition.

Step 9: Choose the files you want to get back, and then click Recover button.

Next, reformat the unmountable Macintosh HD partition and reinstall macOS.

Step 10: Boot the Mac into Recovery Mode.

Step 11: Select Disk Utility from the macOS Utilities menu.

Step 12: Select the unmountable Macintosh HD partition from the sidebar.

Step 13: Click Erase on the top. Here you need to setup the format type and name.

Step 14: Go back to macOS Utilities menu and select Reinstall macOS.

Step 15: Follow the onscreen instructions to complete macOS reinstallation.

Step 16: Reboot your Mac to check if the Macintosh HD partition is mounted.

Still have questions?