External Hard Drive Not Showing Up on Mac

Want to know why your Mac isn’t recognizing external drives? There are many potential reasons why they aren’t showing up on your Mac—from malware to incompatible software. Meanwhile, with MacKeeper’s Find & Fix feature, detecting and fixing many of these issues is easy.

Why is your MacBook not recognizing your external hard drive?

There are many potential reasons your external hard drive fails to work properly with your Mac. They include:

• Your external storage is formatted in a format that isn’t supported by the macOS file system.
• Your connection with the storage is interrupted or non-stable, which means that your USB cable might be loosely connected, damaged, or frayed.
• The main cable (in ~95%, it would be USB to Micro-B)  isn’t in the proper condition or its connectors are not in good shape.
• The data on your external drive has some glitches, preventing your Mac from accessing it.
• macOS isn’t set up properly, or settings have become malfunctioned.
• Your storage has some serious physical intervention, and it could require additional fix steps to extract the data.
• Your Mac may have been compromised by unwanted actions or even malware that performed some tricks, so using MacKeeper’s Antivirus to check for malware activity can help here.

All of these could be why your external hard drive isn't readable on Mac. Thankfully, most of them can be fixed easily.

A note from our experts:

 

When you plug a hard drive into your Mac, you expect it to pop up in Locations in Finder—next to your remote disk and the computer itself. But what if it’s suddenly not there?

 

In just a few clicks, MacKeeper can give your Mac a new lease of life, fixing the hard drive not showing up issue. See what it can do for you:

1. Download MacKeeper, start the app, and click Find & Fix on the left.
2. Click the Start Full Scan button. Wait for the scan to finish.
3. If MacKeeper finds anything wrong, click Fix Items Safely.

Ways to fix: Mac not recognizing the external drive

When you find an external drive not loading on a Mac, there’s no need to panic. Follow our tips, and you should be able to get it working soon enough:

1. Restart your Mac.
2. Edit your preferences.
3. Ensure your cable has sufficient power.
4. Try other devices for power supply.
5. Use Terminal.
6. Engage Disk Utility.
7. Change the format of your HD.
8. Run First Aid.
9. Reset NVRAM.
10. Check the drive in System Information.
11. Run Apple Diagnostics.
12. Try plugging it in differently.
13. Try a different drive.

1. Restart your Mac

The first step whenever you encounter an issue on your Mac, such as an external drive not being recognized, is to restart your computer. Try this:

1. Click the Apple logo in the top-left of the screen, then select Restart.
2. Select Restart again to confirm.

Once your Mac has finished booting up again, you can try accessing your external drive again.

2. Edit your preferences

If you find an external drive isn’t appearing on your Mac’s desktop, you may need to edit your macOS system settings. You can do that by following the steps below:

1. In Finder, select Finder > Settings from the menu bar.
2. In the General section of settings, make sure you tick the boxes next to External disks and Hard disks.
3. Go to the Sidebar and check Hard disks and External disks there as well.

3. Ensure your cable has sufficient power

Some hard drives, especially those that look like a big box or 3.5 storage type, require more power supply than others. However, if your hard drive needs supplemental power, it may not connect at all.

In case your iMac or MacBook isn’t detecting an external hard drive, make sure the light is on and all seemingly empty ports are connected with cables that would fit into the port or connector. If possible, check for picture over the Internet or from the box or papers, swap to another cable or to a different system.

If your iMac or MacBook keeps turning off, too, you may have other power issues you need to look at.

4. Try other devices for power supply

If you find that no matter what type of cable you use, you’re unable to see an external hard drive on Mac, the problem might be in your machine’s hardware. Try using another Mac or Windows device. If only the Windows PC is picking up the external drive, it’s like the disk is using a format that isn’t compatible with macOS. If it works on another Mac, something else is going on, but you’ll eliminate the drive itself as being the cause of the problem.

5. Use Terminal

For average users, the Terminal app is a last-resort solution because they tend to find it complicated. However, it often grants you more power than the front end of macOS, so it’s useful when fixing issues like a Mac not picking up an external hard drive.

Use Terminal to try to force an external to appear:

1. Open Terminal from Applications > Utilities > Terminal. Type in diskutil list. This is a command that extracts information from the system to analyze any volumes and drives attached to your Mac.
2. A list of your disks will appear—search for a line with /dev/disk_ (external, physical)—the underscore signifies a digit assigned to your disk’s identifier.
3. Type in another command—diskutil info disk_, with the digit of the external disk that you’re interested in place of the underscore.
4. If your system recognizes the drive, this action should reveal the information about your drive.
5. Then you can eject it by typing in diskutil eject disk_, with your drive’s assigned digit in place of the underscore. Now, try unplugging your external drive and then reconnecting it.

Important: If you’re running a new version of macOS, you might come across the “Operation not permitted” error when entering a Terminal command. This isn't a software bug—it occurs due to additional System Integrity Protection security measures. The latter can lock down certain areas of the system and only relieve the lockdown during updates. This feature was introduced in El Capitan, so you’ll find it in Sierra, High Sierra, Mojave, Catalina, Big Sur, Monterey, Ventura, and Sonoma.

To fix this error, you need to grant Terminal full disk access:

1. In System Settings, select Privacy & Security > Full Disk Access.
2. Scroll down until you find Terminal. Click the toggle button.
3. Enter your user password and press Return.

6. Engage Disk Utility

Disk Utility often becomes the ultimate fix for a lot of Mac problems, including when your iMac or MacBook can't see external drives any longer. It can help to access and repair some disk issues by checking partition Macs and performing additional checks across the system.

To use Disk Utility, follow these steps:

1. Open Disk Utility from Applications > Utilities. The sidebar on the left will display any external drives—you should be able to view your hard drive there.
2. Click on the volume for a menu to appear. If the drive has been mounted, there will be an option to unmount the device. If you can’t see a volume list, your Mac can’t access the drive at all, and you won’t be able to mount it.

7. Change the format of your HD

Warning: Reformatting will erase all data on the drive. Make sure to back up any important files before proceeding!

Macs primarily use APFS or HFS+ file systems, while Windows computers typically use NTFS. Both macOS and Windows support FAT32 and exFAT, but choosing an incompatible format may prevent your external drive from appearing on your Mac.

To check your drive's format, follow these steps:

1. Open Disk Utility from Applications > Utilities.
2. Select your external drive from the list on the left, then click Erase.
3. Choose a Mac-compatible format (available would be APFS or HFS+ (Mac OS Extended Journaled) or FAT or exFAT) and click Erase. If somehow you’d find UDF there, ignore it, as it’s for those fancy SuperDrive colorful DVD disks.
4. Once the process is complete, click Done.

8. Run First Aid

If your Mac isn’t registering an external hard drive, running First Aid may help to proceed with your Mac disk repair. No matter which version or interface of Disk Utility you have on your Mac, there’s a universal way to reach this goal:

1. Use the key shortcut Cmd + 2 or choose View > Show All Devices, and you should notice additional items appear.
2. Select the first or top-listed item/device in the sidebar.
3. Go back to Disk Utility’s menu bar > File > Run First Aid or click the First Aid button.
4. Select Run.
5. Although a green checkmark could appear, pay attention to the bottom section called Show Details. Expand the section and check whether the procedure was successful.
6. Get the confirmation note and click Done.

Important hints from our tech expert:

 

Sometimes Disk Utility could show you that checkup has been successful, but there could be some minor problems interrupting or causing some inconvenience with your data operations. In other words, there could be red-color messages under the Details dropdown menu despite the green checkmark, like in Step 6 we showed above.

 

In this case, repeat the same actions into the lower items of the external disks list, one by one. Sure thing, make sure that there aren’t any red color highlighted messages under Show Details section. If the operation fails, there will be a reason why—mentioned as a detail.

9. Reset NVRAM

Nonvolatile random-access memory (NVRAM) stores local settings such as volume, screen resolution, and hard drive information. Your Mac’s firmware can primarily access this information before it starts booting when you restart it. At the same time, NVRAM bugs are the source of many glitches, including a hard drive or USB flash drive not showing up.

With Intel Macs, resetting the NVRAM can help to fix all kinds of issues. Here’s how to do it:

1. Restart your Intel Mac.
2. When you hear the startup sound, hold Command+Opt+P+R.
3. This causes your Mac to restart again. When you hear the startup sound for the second time, let go of the keys.

If your Mac uses an Apple Silicon processor (M1, M2, or M3), you can’t reset the NVRAM manually. Your Mac will do it automatically if it detects an issue at startup.

10. Check the drive in System Information

To confirm your external hard drive is being seen by your Mac, we recommend you check the System Information or System Report section, like so:

1. In System Settings, go to General > System Report.
2. Select Storage in the sidebar, then check the list of drives attached to your Mac.

If you don’t see your external hard drive here, you can rule out the possibility that your Mac is recognizing the drive but just not allowing you to access it in Finder. In our expert’s experience, this suggests a problem with the connection to your drive or potential issues with the drive itself.

11. Run Apple Diagnostics

Apple Diagnostics is a tool built into macOS that lets you check your Mac for hardware failures, such as bad hard drives. Find out how to use it below.

On a Mac with Apple Silicon:

1. Press and hold the power button on your Mac.
2. When you see the startup options screen, press Command + D on your Mac’s keyboard.

On an Intel Mac:

1. Turn on your Mac, then immediately press and hold the D key.
2. If this doesn’t work, press Option + D at startup instead.

Pick a language and connect to Wi-Fi, and then wait for Apple Diagnostics to test your Mac. When the process is complete, the test results will be displayed.

12. Try plugging it in differently

Sometimes, external drives connect and function better if you plug them in more slowly or not to the very end. This is due to the power-up sequence of some USB drives or some damage had been done to Mac’s USB port like it could be slightly bent or have some dust or wool. The power contacts of some USB connector differ, whether it’s due to design or the other factor.

Plugging in slowly applies power to the USB device, giving the device extra time to initialize. This ensures the proper order of events and hence mounting of your hard drive. If you find your Mac recognizes an external drive sometimes, but not all the time, this could be the cause.

An explanation from our tech expert: Try another port—Mac USB port/extender’s USB port—or use the other connection method, like switching to a different dongle/extender to fix the connection issue.

13. Try a different drive

If you’ve tried all the methods described above, and macOS still isn’t seeing your external drive, then isolate the problem by plugging in a different external hard drive. If another disk is recognized, the problem might be in the drive itself. Have you recently dropped it or subjected it to water damage? Check for any hardware issues. In the worst-case scenario, you’ll have to replace the drive.

Here are a few reliable hard drives and SSDs that you could use with a Mac device:

How to avoid a situation where Mac is not detecting an external hard drive

You now have a clear idea of what to do if your Mac isn’t reading external hard drives anymore. To make sure you don’t face the same issue in the future, always check that the disk is in the right format for your operating system, that it has a strong enough power supply, and that the connector of your USB cable isn't damaged. However, there are several additional things that you can do to avoid future complications:

1. Make sure the USB port is clean and properly connected.
2. Always properly eject the device.
3. Keep your operating system up to date.

1. Make sure the USB port is clean and properly connected

Dirty or loosely connected USB ports can create short currents. As a result, your Mac might not recognize external hard drives or may read from them inconsistently. It’s common for a connector to get a bit wonky if you’ve used it for a while—the power contacts won’t align correctly.

In this case, your only option would be to get a new cable or, if you’re very persistent, get it fixed. If the connector or the USB port is dusty, you can clean it by blowing compressed air into the port and gently swabbing it with a cotton bud dipped in alcohol solution.

You may also want to reset USB ports on Mac—get our guidance on that.

2. Always properly eject the device

Removing an external drive without safe ejection can corrupt data on it, which in the future can prevent your Mac from finding it. Any operating system employs write caching—files are not immediately written on your hard drive when you transfer it or back it up, but are cached until all the side writing and reading operations are finished.

If the USB device isn't safely ejected while the cache is in use, data can become damaged. Contrastingly, removing it safely clears the cache and stops background operations in the device, protecting you from a situation where your Mac is unable to see the external drive.

3. Keep your operating system up to date

An out-of-date operating system can cause issues for all areas of your computer, including external disks not appearing. Updates improve stability and performance, as well as ensure your Mac’s security and minimize the risk of your files getting corrupted.

To install the latest version of your operating system:

1. Go to the Apple menu at the top of the screen.
2. Select System Settings > General > Software Update.
3. If there’s an update available, you’ll see a notification in the sidebar. Click it, make sure all of your important work is saved, then click Update Now.

Is it time for a new external hard drive?

Hard drives and SSDs don’t last forever, and the more you use them, the more likely they are to break down. When that happens, you’ll find your Mac isn’t able to read the external hard drive. Sometimes, it happens, and you can face inconsistent performance from your external drive. If it’s the case for you, back up important data to another location immediately.

Other times, drives die suddenly, and you cannot retrieve the data stored on them. In many cases, though, when your Mac is struggling to recognize an external drive, the fixes we’ve looked at here will solve the issue. And if you want to save yourself the trouble of searching through settings and folders, you can save time with MacKeeper’s Find & Fix—a fast, easy way to get your Mac in top working condition.