One of the most attractive features of USB drives is the convenience with which they can be used. Most if not all modern computers come equipped with at least one USB port and it is usually simply a matter of plugging the drive into the port. Under normal circumstances, you will have immediate access to the device and the data it contains.

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Unfortunately, circumstances are not always normal when dealing with computers and storage devices. You might be ready to view some photos your friend sent you on a flash drive when you discover that the USB drive is not showing up on your Mac.

If your Mac won’t recognize the USB drive then you cannot access its data, rendering the device useless. Hopefully, you are not subjected to this issue very often, but if you do experience problems when attempting to view a USB drive there are some potential remedies that you can try.

5 Best Ways to Fix a USB Flash Drive That Won’t Show Up on a Mac

Let’s take a look at some of the causes of a flash drive not showing up on a Mac to determine if you can resolve your particular issue. Some of these fixes are very simple while others may involve performing data recovery on a corrupted or damaged drive.

Before trying any of these options, if it is not too much trouble, try restarting your Mac. It is often the most efficient way to deal with the occasional hardware glitch that arises from time to time. If that doesn’t work then read these other options.

1 Physical Connectivity Issues

The first thing to check if your thumb drive is not showing up on a Mac is if the problem is with the particular USB port that you are using. At the risk of stating the obvious, your first move should be to try the device in an alternate USB port available on your machine.

If the device works in the second port it indicates that the first port may be damaged and may need to be replaced or repaired. However, if the drive doesn’t work in any of your USB interfaces you need to look further to determine the problem.

If another Mac is available, try connecting the flash drive to it in order to verify that the USB drive itself is not the culprit. If it will not work on different Macs then it is likely that there is a major issue with the device.

2 Insufficient Power

Your flash drive may not be registering with your Mac due to an issue of insufficient power. This is especially prone to happen if you use a bus-powered USB hub and have multiple devices connected simultaneously. Your Mac or MacBook may not be supplying enough power to adequately service all of the devices.

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The solution here is to try connecting the flash drive directly to the computer’s USB port or employing a self-powered hub that eliminates the power drain on your machine.

3 Failure to Previously Eject a Drive

If your Mac is having problems identifying a flash drive it may be that you did not properly eject a drive that was previously connected to your machine. Failure to eject a USB drive before pulling it out of the port can cause the OS to view the port’s status incorrectly and may impact its ability to be identified and accessed.

4 Update Your Mac’s OS and Firmware

Checking for updates may be one of the easiest ways to open USB ports on your Mac. Firmware updates address a variety of hardware issues and the functionality of the USB ports could well be one of them.

Keeping your software and firmware up to date is good practice even if you are not experiencing problems. It is an essential step in resolving issues when they arise.

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5 Faulty System Configuration

Your system configuration might need to be reset in order to resolve the USB port problem. Here’s how to reset the USB ports on your Mac by resetting two different system components that might be impacting your ability to use the USB ports on your machine.

Reset the System Management Controller (SMC):

  • Follow these steps on a Mac:
  1. Shutdown the machine.
  2. Disconnect the power cord.
  3. Press down the power button and hold it for 5 seconds.
  4. Reconnect the power cord and turn the Mac on.
  • Follow these steps on a MacBook:
  1. Shutdown the MacBook.
  2. Connect the power cord.
  3. Hold Shift+Control+Option and the Power button simultaneously.
  4. Release all the keys at the same time.
  5. Start the MacBook.

If that does not work you can try resetting the PRAM/NVRAM. The Parameter Ram and the Non-volatile RAM contain information concerning the USB ports on your Mac.

Follow these steps to reset these memory locations:

  1. Shutdown the computer.
  2. Restart the machine while holding down Command+Option+P+R.
  3. Hold down the keys until the screen flashes and you hear a sound.
  4. Listen for the chime and let the computer boot normally.

Recovering Data From a Corrupted or Crashed Flash Drive

It may be that the reason you cannot access the data on the flash drive is due to data corruption. Using data recovery software you can attempt to restore the data if you can get the system to recognize the drive so the recovery software can work on it.

Disk Drill USB drive data recovery software for Mac is an excellent solution that gives you a great chance of recovering your files from a damaged or corrupted drive.

In order to recover data from a flash drive or other USB connected drive using Disk Drill, follow these steps:

  1. Download and install Disk Drill on your Mac. You can use the free version of the software to determine if your files can be recovered before upgrading to the Pro version of the application.
    Disk Drill
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  2. Attach the USB or flash drive which contains the data that is to be recovered.flash drive not showing up on mac
  3. Launch the program and provide your administrator’s password if prompted.USB drive not showing up on mac
  4. Select your flash drive from the list of disks that Disk Drill can access. Click the ‘Recover’ button to initiate Disk Drill’s scanning algorithms which will search your drive sector by sector to salvage as much data as possible.thumb drive not showing up on mac
  5. Review the list of recoverable files returned by the application and determine if you are satisfied with the results.mac not recognizing a flash drive
  6. If the preview indicates that the files you wish to recover can indeed be salvaged you will need to upgrade to the Pro version of Disk Drill to finish the actual file to transfer photos from Mac to external hard drive
  7. Select a location where you will store the files that are being recovered. Do not attempt to save the files to the flash or USB drive in question. Select a new location on your computer where the files can safely be stored.mac do not recognize a flash drive
  8. Click ‘Recover’ again and Disk Drill will perform the files recovery, saving the data to the new location you have previously selected.mac won't recognize USB

Disk Drill can be a lifesaver in situations where you cannot access files due to disk corruption or damage. It can also recover files that have been accidentally deleted or from a disk that was inadvertently formatted. It is definitely worth checking out when faced with the prospect of irretrievable data on a USB or flash drive.

Problems with your USB ports can be extremely annoying but can usually be resolved through one of the techniques discussed above. We hope that you regain access to your data in a timely manner.

Arthur Cole

Arthur Cole is a freelance content creator. He also has a more than 10-year experience in program development for macOS, Windows, iOS, Android.Arthur Cole is a writer with deep expertise in programming, who can easily...

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Approved by
Brett Johnson

This article has been approved by Brett Johnson, Data Recovery Engineer at ACE Data Recovery. Brett has a Bachelor's Degree in Computer Systems and Network, 12 years of experience.