Solved: Restore Data from Unmounted External Hard Drive on Mac

If you're unable to access your external hard drive on Mac, including USB, Thunderbolt, firewire, and more, you can follow a similar process to fix the issue. To make your device accessible without losing any data, you can try the solution provided for fixing unmounted external hard drives, which can also be applied to other types of external storage devices on Mac. By following this process, you should be able to access your external hard drive on your Mac desktop.

Workable Solutions	Step-by-step Troubleshooting
Part 1. Check Drive	Check external hard drive cable, the USB port on Mac, and its state in Disk Utility...Full steps
Part 2. Mount "Unmounted" Drive	Open Disk Utility > Select the unmounted external hard drive > Select "Mount"...Full steps
Part 3. Recover Lost Data	If you lost drive data, run Deep Data Recovery for Mac to bring it back...Full steps
Part 4. Change Drive Format	If Mac is not compatible with the drive format, use Disk Utility to erase it to Mac OS Extended...Full steps

If you've encountered an issue where your external hard drive won't show up on your Mac desktop, don't worry - you're not alone! This problem can occur when the disk is unmounted, but don't worry, your data is safe. To resolve this issue, you can follow the steps outlined in the original text to force the unmounted external hard drive to show up on your Mac desktop without losing any data.

You can follow to resolve the same issue on your own now.

Part1. Check External Hard Drive

You should check the external hard drive for any physical damage, file system corruption, or power issues that may be causing the device to unmount. This can be done by checking the drive's LED lights, power cord, and cable connections.

Follow through the checking tips here and find out the problem:

# 1. Check the cable

Check if the external hard drive cable is securely plugged into the Mac and the drive itself, and if the drive is properly connected to the Mac via its cable. If not, re-plug the cable and reconnect the drive. If the issue persists, the connection cable may be damaged and needs to be replaced.

# 2. Switch USB port

If a USB port is not working, try replacing it with a new one and reconnecting the external hard drive. If the external hard drive shows up after the change, the issue is resolved. If not, proceed to the next troubleshooting step.

# 3. Check disk file system

A Mac computer can read HFS+, NTFS, FAT32, exFAT, and APFS file systems. If your external hard drive has a different file system, you can reformat it to a format that's readable by Mac.

# 4. Check Disk Utility

Open Disk Utility by navigating to Finder, then Applications, then Utilities, and finally double-clicking on Disk Utility to bring it up.
Check if the external hard drive is visible.

Check external hard drive state in Disk Utility

If the external hard drive icon appears below the External section, you can simply follow the next two parts to mount your external hard drive and recover your data with ease. However, if the icon doesn't appear, it may indicate a problem with the drive, and you may need to repair or replace it. If the drive has failed or crashed, it may be beyond recovery.

Part 2. Mount 'Unmounted' External Hard Drive

Mac Disk Utility is a professional tool that helps resolve most disk management issues on Mac, functioning similarly to Disk Management in Windows OS.

When a storage device becomes unmounted as shown on this page, Disk Utility also assists mounting the device and fixing it back to a healthy state:

Step 1. Open a new Finder window, click "Application" and open "Utilities".

Step 2.To access the Disk Utility, locate and double click on it to launch it. Then, navigate to the left panel and find the external hard drive under the External section.

The external hard drive is greyed out and marked as "Untitled" on the Mac computer, indicating it's not mounted.

Unmount external hard drive.

Step 3.In the Disk Utility window, select the untitled external hard drive and click the "Mount" button from the Disk Utility bar.

Unmount external hard drive and make it recognizable.

After restarting the Mac, reconnect the external hard drive and you should be able to access and use your existing data again.

If the data on your external hard drive is corrupted, you can try using data recovery software to restore your files. However, if the damage is too severe, you may need to seek professional help from a data recovery service.

Part 3. Restore Lost Data after Mounting External Hard Drive

If an external hard drive becomes inaccessible after being mounted on a Mac using Disk Utility, it's likely due to an issue with the device itself, rather than the mounting process. This could be a problem with the drive's hardware or its connection to the Mac.

To recover data from a Mac external hard drive, the best approach is to use professional data recovery software. A suitable option is Deep Data Recovery for Mac, which can scan and recover all existing data, including lost files, from the external hard drive on Mac OS X and macOS systems.

Free Download
Windows 11/10/8/7, 100% Secure

Follow the step-Here's a one-paragraph, step-by-step guide to recover data from your external hard drive:

Step 1. To recover data from your USB flash drive on a Mac, connect the drive to your computer, then launch Deep Data Recovery for Mac. Select the desired file types and click "Next" to begin the recovery process.

Select file types that you want to recover

Step 2. Select the flash drive and click "Scan" to search for lost files on it.

select the flash drive where data lost and click scan

Step 3. After a quick scan and deep scan, all files will be presented in the left panel in the scan results.

click recover now button to recover lost flash drive data

Step 4. Select the files you want to recover, and click the "Recover" button. Do not save the recoverable files to the USB drive to avoid data overwriting.

To ensure your external hard drive is secure to store files again, first, make sure it's properly connected to your computer and turned on. Next, check that the drive is recognized by your computer by looking for it in the File Explorer or Disk Management on Windows, or the Disk Utility on Mac.

Bonus Tip: Format External Hard Drive for Mac Compatibility

If an external hard drive's file system is unrecognizable on a Mac, it may not mount, and if it does, it may still be inaccessible. In this case, formatting the drive for Mac compatibility is necessary.

Here are the steps:

Step 1. Connect the external hard drive to your Mac, then open the Applications folder, navigate to Utilities, and double-click the Disk Utility app to launch it.

Step 2. In Disk Utility, select the external hard drive and click "Erase" at the top pane.

Erase unmounted external hard drive.

Step 3. To format the external hard drive, select it in the "External Devices" list and click on the "Format" button next to "Mac OS Extended (Journaled)".

Step 4. Rename the drive if you want and click "Erase" to confirm again.

Erase unmounted external hard drive to Mac compatible.

After restarting your Mac, reconnect your external hard drive and you should be able to access and save new data on it again.

People Also Ask

Some Mac users may still be unclear about mounting and unmounting issues on their Mac computer. Questions like "What is mounting and unmounting on Mac?" or "How to mount and unmount external drive on Mac?" are frequently asked.

1. What does unmounted hard drive mean?

A mounted drive on a Mac computer can be automatically detected by the operating system, allowing users to directly access and utilize the files saved on it.

When a hard drive is unmounted, it will not be recognized by the Mac operating system and will not show up on the computer.

2. Why won't my external hard drive mount on Mac?

The external hard drive may become unmounted on a Mac due to various reasons, including hardware issues such as faulty cables or a malfunctioning drive, software problems like corrupted system files or outdated drivers, user error from improper ejection or sudden power loss, and file system inconsistencies caused by sudden shutdowns or system crashes. Additionally, compatibility issues between the external drive and the Mac's operating system, or conflicts with other devices connected to the Mac, can also lead to the external hard drive becoming unmounted. Furthermore, the external drive may become unmounted if it is not properly formatted or if the drive's file system is not compatible with the Mac's operating system.

Hardware and connection issue
Corrupted disk
Incorrect formatting of the disk
Software conflict
Malfunction of macOS

We suggest backing up essential data more regularly, with even two copies being acceptable, to prevent data loss in case of a system failure or other issues.

3. How do I mount an unmounted hard drive or external hard drive Mac?

To access your external or internal hard drive on a Mac, first ensure that it's correctly connected to your computer.
After rebooting the Mac computer, open Disk Utility and locate the unmounted drive. Select the drive and then choose "Mount" from the top menu.
Last, reboot Mac computer again to keep all the changes.

After using Deep Data Recovery for Mac, you should be able to access your device and use the saved data again. If your files are missing on the mounted drive, the software is always ready to help.