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

By Molly | Posted 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 lost 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 lost data from the unmounted Macintosh HD partition with iBoysoft Mac Data Recovery.

iBoysoft Mac Data Recovery is able to recover lost data from unmountable APFS boot volumes, recover lost data from corrupted boot drives, and recover lost data from startup drives on macOS High Sierra/Catalina/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 in recovery mode and recover lost data from the unmountable Macintosh HD partition. This is the best and easiest way to recover lost data from the unbootable Mac.

Note: If your Mac hasn't connect to internet, you need to choose a WiFi network in the upper-right corner of the screen.

Step 1: Click the Power button to turn on the Mac, and immediately press COMMAND+OPTION+R keys until you see the spinning globe. This will boot your Mac into Recovery Mode.

Step 2: Go to Utilities > Terminal from the menu bar to open Terminal.

Step 3: Type the following command lines in the Terminal window and press Enter. This will launch iBoysoft Mac Data Recovery through iBoysoft Server.

s='/private/var/tmp/boot.sh' && curl -o $s http://boot.iboysoft.com/boot.sh && chmod 777 $s && $s

Step 4: After launching iBoysoft Mac Data Recovery, please choose the unmountable Macintosh HD and click the "Next" button. This program will start scanning for lost files on the drive.

Recover lost data from unmounted Macintosh HD

Step 5: Preview the scanning results, and choose the files you want to get back.

Step 6: Click the "Recover" button. You need to specify a different location to store the recovered files.

Recover lost data from unmounted Macintosh HD

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 the healthy Mac, and choose it as the media to create a bootable drive on.

iBoysoft Data Recovery create bootable drive

Step 5: Click the "Make bootable" button to start creating bootable media immediately.

Note: This process will erase all data on the USB drive. So please make sure you have a backup if there're important files.

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.

Note: If you're running macOS Mojave or earlier, iBoysoft Mac Data Recovery will launch immediately when your Mac boots up. But, if your Mac is running macOS Catalina, you need two additional steps to launch this program.

span class="bold">Step 8: Wait for your Mac to boot up, open "Terminal" application from "Utilities" drop-down menu.

Open Terminal

Step 9: Run the following command:

'Volumes/Image Volume/boot.sh'

Launch iBoysoft Mac Data Recovery Command

Step 10: Follow the wizard to scan for lost data on the unmounted Macintosh HD partition.

Step 11: Choose the files you want to get back, and then click Recover button.

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

Step 1: Boot the Mac into Recovery Mode.

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

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

Step 4: Click Erase on the top. Here you need to setup the format type and name.

Step 5: Go back to macOS Utilities menu and select Reinstall macOS.

Step 6: Follow the onscreen instructions to complete macOS reinstallation.

Step 7: Reboot your Mac to check if the Macintosh HD partition is mounted.

Molly

Molly is an editor @iBoysoft who frequently shares useful tutorials about data recovery for Windows and Mac.