How to repair an external hard drive greyed out in Disk Utility?

By Vivian | Posted to Mac Data Recovery on Jan 9th, 2019 |

I've been Googling for solutions for the past seven hours. The thing is, I was about to back up and of course, My External Hard Drive in Disk Utility Is Grayed Out!!! My life lives on this disk. I want to also mention that the computer reads the disk. I know this because it appears in Disk utility, but it's grayed out. Someone helps me.

It is possible that you plug an external hard drive into Mac as normal but can't open it. So, you launch Disk Utility to check this drive, only to find that the external hard drive greyed out in Disk Utility. You can calm down first, because if you see external hard drive greying out in Disk Utility, your external hard drive at least has no hardware errors. Now, read this page to repair your external hard drive that greyed out in Disk Utility.

Why does the external hard drive grey out in Disk Utility?

Sudden power failure, unsafe ejection, virus attacks, etc. will damage the file system of the drive. If the file system is corrupted too seriously to be read by the operating system, your external hard drive, such as WD My Passport will be greyed out in Disk Utility.

Tutorial to repair external hard drive greyed out in Disk Utility

Solution 1: Try to mount the external hard drive

Sometimes, your external hard drive greyed out in Disk Utility just because it was not mounted. Try to mount this external hard drive in Disk Utility manually. If the external hard drive is not mounting in Disk Utility still, reboot your Mac and try again.

Solution 2: Repair this external hard drive with First Aid

Manually mount doesn't work? It could be some minor file system errors in this external hard drive. Fortunately, the built-in utility First Aid will check and repair minor file system errors.

Step 1: Go to Utilities, find Disk Utility and run this program.

Step 2: Click "Show all devices" in View option and select this external hard drive in the left sidebar.

Step 3: Click "First Aid" in the top menu of Disk Utility.

Step 4: Click "Run" to check and repair errors in this drive.

Solution 3: Reformat this external hard drive

Suppose First Aid failed on the external hard drive and you still can't open it, the file system of the drive could be seriously corrupted. Reformatting can fix the file system corruption, but it also will erase all data on it. Therefore, if you didn't back up data before, the safe choice is to recover data firstly with reliable data recovery software, like iBoysoft Mac Data Recovery. If data loss is not a hassle for you, you can just skip to reformatting.

iBoysoft Mac Data Recovery is professional and free Mac data recovery software, which is able to recover data from unmountable/formatted/inaccessible external hard drives. It can recover data from APFS, HFS+, HFS, FAT32 and exFAT external hard drives, USB drive, flash drive, SD cards, CF card, memory cards, etc. This software also can undelete documents, pictures, emails, music, etc. from Trash on macOS Mojave/High Sierra.

Step 1: Recover data with iBoysoft Mac Data Recovery

1. Download, install and launch iBoysoft Mac Data Recovery on your Mac.

Recover data from external hard drive on Mac

2. Select the external hard drive that is greyed out in Disk Utility and click "Next" to scan for data stored on this drive.

3. You will see the scanning results in the left sidebar with three categories: files path, type and time. Please double click these files to preview them.

4. Select the files you want to get back and click "Recover" recover them from this external hard drive. Remember to save these files to another healthy drive for good.

Step 2: Reformat this external hard drive with Disk Utility

1. Launch Disk Utility.

2. Click the external hard drive that greyed out in the left sidebar.

3. Click "Erase" and fill in the information that the wizard asked, then click "Erase" to complete this process

It will be great if this article has helped you repair the external hard drive that greyed out in Disk Utility.


Vivian likes to share technical tips and solutions with people, especially in macOS and Windows data recovery tricks. Being a part of @iBoysoft, she has solved many computing and technological problems for readers with ease.

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