External Hard Drive Is Not Mounting on a Mac: How to Fix and Recover Data

I. The reason why the mobile hard disk cannot be loaded on Mac

Generally, when a user connects a mobile hard drive to a Mac computer, the hard drive will be displayed on the desktop and in the “Finder” for users to read and write data normally. So why sometimes I can’t find the newly connected external hard drive in the desktop and “Finder”? The reason may be USB data cable, USB port, setting problem; or the mobile hard disk is not properly formatted, damaged/faulty; sometimes it is caused by improper operation, such as accidental ejection, or directly unplugging the mobile hard disk, and it cannot be loaded after reconnecting.

The following will provide some solutions for the above reasons that may cause the mobile hard disk to fail to load, and hope to help you solve this problem.

II. How to solve the problem that the mobile hard disk cannot be mounted on Mac?

1. Replace the USB data cable or USB port and connect again

When the mobile hard disk cannot be loaded, the first thing to eliminate is the connection problem. Please replace the USB data cable or USB port and connect again to check whether the mobile hard disk can be loaded normally. Note: Please safely eject the mobile hard disk. If you cannot find the option of safe ejection, you can also shut down and then remove it.

2. Change the Finder preferences

If the USB data cable or USB port problem is excluded, but the mobile hard disk is still not displayed on the desktop or in the “Finder”, you can try the following settings:

Step 1: Open the “Finder”, click (Finder) – (Preferences) on the top menu bar on the right.

Step 2: Under the (General) tab, check (External Hard Drive) in “Show these items on the desktop”.

Step 3: Switch to the (sidebar) menu, check (external disk) under “Location”, if there are no other problems, after setting, the mobile hard disk will be displayed on the desktop and in the Finder.

3. Mount the removable hard disk in Disk Utility

After troubleshooting the connection and setting problems, you can enter (Disk Utility) to check the mounting status of the mobile hard disk. If it is mounted, it will display (Uninstall) in the top menu of Disk Utility. If it is not mounted, it will display the (Mount) option.

Step 1: Find and click (Disk Utility) in the launchpad; you can also click (Finder) > (Applications) > (Utilities) to find and open (Disk Utility).

Step 2: Select the target mobile hard disk in the left sidebar, and click (Load), and wait for the loading to complete under normal circumstances. If the loading fails, please try the following method of entering commands in the terminal to load.

4. Enter the command in the terminal to mount the mobile hard disk

Step 1: Connect the mobile hard disk to the Mac computer, and open the (terminal) on the computer.

Step 2: Enter the following commands and press the (Enter) key each time you enter a command.

Enter (diskutil list) to list the disks in the computer, and then determine the disk number according to the disk capacity or disk name and other information.

If you confirm that the mobile hard disk number is (/dev/disk1) (please replace the hard disk number according to your actual situation), you can enter (sudo diskutil mount /dev/disk1) to mount the hard disk.

If the loading fails, please enter (ps aux | grep fsck) to check whether the fsck process list pops up. If so, please enter (sudo pkill -f fsck) to kill all fsck processes, and then enter (sudo diskutil mount /dev/disk1) or unplug the hard disk and reconnect it, then the mount will be successful.

Generally, this step can solve most of the problems that the mobile hard disk cannot be loaded. If it still cannot be solved, then the mobile hard disk may be damaged or not formatted correctly. You need to use the (First Aid) and (Erase) functions of Disk Utility to deal with it. However, these two methods may damage or clear the data in the hard disk. It is recommended to use the following data recovery software to recover/extract the data before continuing the subsequent operations. If your mobile hard disk can transfer data through other Mac or Windows computers, you can skip the following data recovery/extraction methods and directly view the relevant introductions of the (First Aid) and (Erase) functions of Disk Utility.

5. Use Renee Undeleter to restore/extract mobile hard disk data

Rene.E Laboratory ™ data recovery software It is a software specially used to restore various data files. When you accidentally delete important files, empty the recycle bin, or format the disk/storage, you can use this tool to retrieve the lost data. The software covers four functional modules, including file recovery, format recovery, partition recovery and image creation, which can help you solve all data loss problems in an all-round way. This software has two versions for Windows and Mac. As long as you can see that the mobile hard disk has been successfully connected to the Mac computer in Disk Utility, you can use this software to scan the mobile hard disk and restore/extract data.

Step 1: Download, install and run Renee Undeleter on a Mac computer, and select the (Format Recovery) option on the main interface. (You can also choose (partition recovery), this function will scan the complete hard disk partition)

Step 2: Next select the hard drive partition where you want to recover data. After the selection is complete, click (Next).

Step 3: Then wait for the scan, the scan time will depend on the size of the hard disk partition. During the scanning process, you can double-click to preview the file. If you have found the file you need to recover, you can check it and click the (Recover) button. At this time, the scan will be terminated to start recovering the file. You can also wait for the scan to end, select the files to be restored from the scan results, and then click the (Restore) button to restore the files to other disks.

6. Use the First Aid function of Disk Utility to repair mobile hard disk errors

Step 1: Find and click (Disk Utility) in the launchpad; you can also click (Finder) > (Applications) > (Utilities) to find and open (Disk Utility).

Step 2: Select your hard disk in the list on the left, and then select the (First Aid) function above.

Step 3: After clicking (First Aid), a confirmation window will pop up, from which we can learn that the “First Aid” function will check the volume for errors, and then repair the volume, please click (Run) to start the hard disk checking and repairing process.

7. Erase the removable hard drive in Disk Utility

The (erase) function in Disk Utility is equivalent to the format function in Windows system. It can change the file system of the hard disk to be recognized by the Mac system. In addition, it can also clear all the data on the hard disk, thereby solving some hard disk failure problems. Note: Please try to connect the hard drive to another computer for data backup before operation.

Step 1: Find and click (Disk Utility) in the launchpad; you can also click (Finder) > (Applications) > (Utilities) to find and open (Disk Utility).

Step 2: Select the target mobile hard disk on the left, then click (Erase) on the top, select the file system format of the hard disk in the pop-up window, and then click (Erase).