How to repair unmounted disk on macOS/Mac OS X?
I have a 2TB hard drive, disk utility is showing unmounted. There are many important documents stored on it, how to repair unmounted disk on Mac computer so that I can access these documents again?
There are several solutions to repair unmounted disk on Mac computer.
Solution 1: Repair unmounted disk Mac with disk utility
Mac OS X operating system built-in tool: disk utility has the ability to repair unmounted disk. Disk Utility can repair common disk issues, ranging from corrupt directory entries to files left in unknown states, usually from power outages, forced restarts, or forced application quits.
We can find disk utitily in Utilities from Application folder. After opening disk utility, please select unmounted disk and then click First Aid. Fist Aid can check the volume for errors and then repair the volume if necessary. After repairing with disk utility, the unmounted disk will be mountable, but sometimes, disk untility cannot repair unmounted disk Mac. In this situation, the best way is to recover lost data from unmounted drive and then reformat it.
Solution 2: Repair unmounted disk Mac with the 3rd-party tool
There are three tools (Same as disk utility) which can repair unmounted disk on Mac computer, but they still fail to repair unmounted disk in some situations.
Stellar Volume Repair - Repair volume errors, rebuild corrupted volume directory, repair disk permissions and corrupted external hard drive.
Alsoft DiskWarrior - A disk repair and recovery tool resolves existing disk damage by rebuilding your disk directory using data recovered from the original directory, thereby recovering files and folders that you thought were lost.
FSCK command - Like the Disk Utility, FSCK command is also an inbuilt feature of Mac OS X, but it is a command line based utility. You can have a try and run this command on the terminal in order to repair unmounted disk.
However, these disk repair tool still fails to repair unmounted disk in some situations, so data recovery from unmounted disk is still the best way.
Solution 3: Recover lost data from unmounted disk
M3 Mac Data Recovery is a free data recovery software which can recover lost data from unmountable, unreadable, unrecognized, corrupted, formatted disk and recover deleted files even if emptied Mac trash in macOS Catalina 10.15/10.14/10.13/10.12 and Mac OSX 10.11/10.10/10.9/10.8.
Tutorial to recover lost data from unmounted disk with M3 Data Recovery for Mac
Step 1: Download and install M3 Data Recovery for Mac on your Mac computer.
Step 2: Connect unmounted disk to your Mac computer and then run M3 Data Recovery for Mac.
Step 3: Select the unmountable hard drive or volume.
Step 4: M3 Data Recovery for Mac is scanning the lost data from unmounted disk.
Step 5: Select the found data and then click Recover to save them.