Fix External Hard Drive not showing up, working, recognized on M1/M2 Mac

The unveiling of the M1 chip probably indicates the end of the Intel-based MacBooks in some depth. Therefore, many users ordered the new M1 Mac mini, MacBook Air, and MacBook Pro. But some are experiencing a server Samsung external hard drive issue - the Samsung portable hard drive seems to be not working on an M1 Mac. And some even find that the 'Disk Not Ejected Properly' notification keeps popping up on Mac while the Samsung external hard drive connects to the Mac well.

Specifically, users are also reporting those issues:

This post explains why you encounter these disk issues and how to make your Samsung external SSD work again.

Let's start with a better understanding of the M1 chip on your Mac, which does more with less fixing the external hard drive not mounting on the M1 Mac issue.

Knowing the new M1 chip on your Mac

The application of multiple chips to deliver different features like processor, I/O, security, and memory has been changed in M1 Macs. Everything is highly integrated into a single system on a chip (SoC) packed with multiple transistors.

Meanwhile, all M1 Macs come with the new macOS 11 Big Sur out-of-the-box. It's a joined force when it comes to running macOS Big Sur software on the advanced M1 chip. Such a combination brings more simplicity, high efficiency, faster performance, better battery life, and advanced security to your M1 Mac.

With Rosetta 2, Apple will take the next two years to shift from Intel-based Macs to Apple silicon Macs universally, but during this time, incompatibility in software and hardware indeed happens.

This makes sense why some Samsung external hard drives run perfectly while some don't even get recognized on M1 Macs.

While the point is, how to fix it if Samsung or other external SSD won't mount on M1 Mac?

Guide to make external hard drive work on M1/M2 Mac

Many components are involved in mounting an external hard drive on Mac computers, especially if there is no USB 3.0 but USB C ports on the Machine. So, it's strongly advised that you follow the following part one by one to isolate the problematic part.

1. Check the external hard drive in System Information

If you see the LED on it randomly toggles between blue and red but the drive doesn't seem to mount, check it in the System Report for power acquisition.

Click on the Apple logo > About this Mac >  System Report, and then choose USB or Thunderbolt based on if you have used a USB hub.

Two circumstances you might see in System Information:

① The Samsung portable SSD is detected with the required power.

This barely means that your external drive has no hardware issue, then the unmountable SSD is a result of software or file system issues. To fix it, you need to start from solution 4.

② The Samsung portable SSD is not showing up here, or it lists but is severely underpowered.

If the M1/M2 Mac doesn't detect your drive in System Report, you may move on to check problems from scratch, including USB ports and cables in the next part.

2. Check USB ports on your M1/M2 Mac

MacBook Air and MacBook Pro models with Apple Silicon M1/M2 chip have two Thunderbolt/USB 4 ports. But they are not enough for multiple hard drives and are not convenient for USB 3.0 hard drives, which forces many users to seek a USB hub or USB adapter.

However, you may get into trouble in mounting external hard drives due to such a hub. If your Samsung external hard drive is not working on M1/M2 Mac, try the following workarounds.

• Use the Thunderbolt/USB 4 port on your Mac directly without a hub
• Try a different Thunderbolt/USB 4 port on your M1 Mac
• Plug only one external device on the USB hub for a dedicated power supply
• Try a different USB port if you use a USB hub
• Make sure the USB port is not damaged, dusty, deformed for a used USB hub

3. Try a different cable to connect the external hard drive

For better compatibility with the host device, manufacturers like Samsung and Seagate will include USB Type-C to C cable and USB Type-C to A cables in the box. But you possibly also bought a white Apple adapter cable.

If your external device doesn't mount with one of these cables, first figure out what type your external hard drive uses, and then try another cable with or without the USB hub.

4. Check if your external hard drive is encrypted

Samsung portable T5 and T7 SSD have optical password protection with AES 256-bit hardware encryption. So, if the Samsung SSD is password locked out of the box using Samsung Portable SSD Software, you can first unlock it using that specific software. Also, you can wipe the disk if you have no data on the SSD.

Another case is that you know your Samsung external SSD is password protected.

However, the Samsung Portable SSD Software doesn't work on the M1/M2 Mac computer. As a result, you have no way to access your SSD but receive the "No Samsung Portable SSD is connected." message.

Then, the solutions in the rest of the article will help.

5. Update to the latest external hard drive Software and Firmware

Though the external hard drive is recognized by macOS Big Sur on M1 Mac, you could also have an issue in opening this disk. You are unable to put in your password to unlock the SSD if the software is outdated, or worse, the software won't even launch for the incompatibility with M1 Mac.

Here is how to fix it:

6. Run First Aid to repair external hard drive on M1/M2 Mac

If the software is good, well, you should keep an eye on the SSD itself. Occasionally, the SSD won't mount in Disk Utility, or it shows a raw device without any partitions.

Then, the external hard drive is suffering from file system corruption or partition table damage issues. You can try First Aid to check and repair the drive on your M1/M2 Mac.

7. Update macOS Big Sur to the latest version on your M1 Mac

You probably bought the M1/M2 Mac at a time when macOS Big Sur is not revised for a new version, macOS 11.0.1 have fixed some macOS Big Sur problems.

Therefore, you can go to system preference to check if any software update available. It may help fix the external not working issue.

8. Recover data and reformat the external hard drive

You don't really have to erase your drive unless all solutions don't make a difference. Reformatting will wipe the drive (including your data on this SSD) and give it a fresh start.

Therefore, you can first get your files off (if you have) the corrupted SSD and then reformat it as the following guide.

First: Recover data from external hard drive on M1/M2 Mac

Not only Samsung Portable SSD, hard drives from Seagate, WD, Toshiba, or other manufacturers could also have data loss problems on M1/M2 Mac.

To recover deleted or lost data from the external hard drive, a recommended plan is to use a hard drive recovery tool compatible with M1/M2 Mac, for example, iBoysoft Data Recovery for Mac.

Second: Reformat the external hard drive on your M1/M2 Mac

The external hard drive not working on the M1/M2 Mac may not be the real panic, but the data loss is. The workarounds in this post should be able to make your external hard drive work on M1/M2 Mac again without data loss.

If you have a hard drive from other brands, the troubleshooting process is basically the same, except for the Samsung proprietary software.