Macintosh HD greyed out in Disk Utility, how to fix and recover data?
"Macintosh HD greyed out in Disk Utility" means Macintosh HD not mounted in Disk Utility, so following solutions are used to solve this problem.
Solution 1: Repair unmounted Macintosh HD with disk utility
1. Restart Mac computer, held down command R, select Disk Utility from macOS utilities and click Continue..
2. Please select unmounted Macintosh HD and then click First Aid. Fist Aid can check the volume for errors and then repair the volume if necessary. After repairing it with disk utility, the unmounted Macintosh HD will be mounted, but sometimes, disk untility cannot repair unmounted disk. In this situation, the best way is to recover data from unmounted drive and then reformat it.
Solution 2: Recover data from unmounted Macintosh HD
M3 Mac Data Recovery is the professional Mac data recovery software which can recover data from unmounted Macintosh HD, external hard drive, recover deleted/lost files emptied from Trash, recover data from unreadable/formatted/corrupted drive, recover data from deleted/lost APFS partition, etc. in macOS 10.14/10.13/10.12 and Mac OS X 10.11/10.10/10.9/10.8/10.7.
In this situation, please create a bootable drive of M3 Mac Data Recovery to recover data after Mac computer won't boot. Refer to tutorial: How to recover data from unmounted drive?
Solution 3: Reformat unmounted Macintosh HD with disk utility
If there is no important data stored in Macintosh HD or we have recovered lost data successfully, please reformat this unmounted Macintosh HD wtih following method:
Step 1: Launch Disk Utility from Utilities.
Step 2: Click the icon for your unmounted Macintosh HD in the sidebar on the left.
Step 3: Click the Erase tab along the top of the window and enter the related information.
Step 4: Click the Erase button.
Solution 4: Send it to a local data recovery professional for help
If solution 1, 2 and 3 fail to fix Macintosh HD greyed out in Disk Utility, Macintosh HD should have hardware issue, please send it to a local data recovery professional for help if you have important data.