Sep 14, 2015  If your Mac doesn’t boot from an external volume or the drive doesn’t show up in Startup Manager even though it contains a bootable copy of OS X, it might need repair. The first order of business should be attempting to repair disk permissions in Disk Utility. In the worst case scenario, you might need to reinstall OS X on the external volume. Nov 17, 2019  Sometimes Mac won't boot from USB as expected. If you are unable to select a different startup disk, it's possible that your disk is not showing up in Startup Manager. If you try Method 1 above but don't see your USB drive listed there, it could mean one of the following problems.

• Mac Os Usb Disk Not Detected
• Mac Os On Usb Stick
• Install Mac Os From Flash Drive

Summary

Does your Mac not recognize a USB drive? Is the USB flash drive not showing up on Mac after inserting it in the USB port? Find solutions here. Download EaseUS Data Recovery Wizard for Mac when you want to recover data from a USB drive not recognized.

Mac Won't Recognize USB, What Should You Do?

1. Jul 31, 2018  Make sure your disk is bootable. Volumes that aren’t bootable and don’t contain a copy of a valid operating system aren’t listed in Startup Disk or Startup Manager. Make sure the external drive you’re trying to start from contains a usable operating system. Boot Mac from USB Mac Startup Disk.
2. Dec 10, 2018  External drives are a cheap way to expand storage without having to replace the internal hard drive. Just connect it via USB or Thunderbolt and it appears in Finder. From there you can do pretty much whatever you like with it. If it doesn’t show up in Finder,though, it will surely show up in the Disk Utility within Utilities.
3. Jan 09, 2020  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.
4. If your Mac is really old - as in so old it's running Mac OS X Snow Leopard or older - it will not have a Recovery partition, the only way to reinstall the OS is to use the discs that shipped with.

Commonly, when you insert a USB drive in the USB port on a Mac computer, the drive will soon appear on the desktop or hide in the Finder, letting you access, view, and manage data on it. Did you come across the situation that no matter how many times you try to connect the USB drive with a Mac computer, the USB drive is not showing up anywhere? Why this time Mac won't recognize a connected USB you may wonder. Though not a usual thing, the issue of an external hard drive or flash drive not showing up on Mac happens sometimes. What should you do in this circumstance? What are the effective solutions to make your USB drive show up again?

This page basically covers all the possible fixes for USB not showing up on Mac, which also applies to the similar issues of other storage devices like an external hard drive not showing up on Mac, flash drive not showing up on Mac, SD card not showing up on Mac, etc. Take a quick glance at the main content and directly jump to the part you're most interested in.

10 Fixes for USB Not Showing Up on Mac

The reasons behind the problem of a USB device not showing up are various, including the USB port is not working, USB drive corruption, virus infection, macOS faulty, etc. So, to figure out the effective solutions for your own case, you need to take time to have some basic check, exclude the irrelevant issues, identify the potential risk, and finally solve it!

Fix 1. Change the USB-to-Mac connection way

Have you tried to restart your Mac once or twice? Before taking further measures, don't forget the most efficient way to tackle commonplace hardware glitches that arises from time to time. If this operating system restarting fails to solve the current problem, move on to check the physical connectivity issue step by step.

Step 1. Plug the USB drive out from the not working USB port and change to the other USB port. Try all the available USB ports on your Mac.

Step 2. Did you use a USB connection cable or a USB-C adapter? If yes, take the USB drive out, and directly plug it in the USB port.

Step 3. Is there the other Mac computer available to you? If yes, try to connect the USB drive to this computer. Is it showing up normally?

Step 4. For SD card owners, the common way to connect an SD card to a Mac needs a card reader. If changing the USB ports did not work, try to change a card reader for a new round of tests.

The four steps of troubleshooting a USB drive not showing up on Mac are very basic, however, quite helpful in most cases. Each step can help us exclude the issues of a bad/loose connection, a not working USB port, a lack of power, and other superficial phenomenons.

Fix 2. Change settings for Mac detecting an external hard disk on the desktop

Occasionally, your Mac has already recognized the USB flash drive but not shown it on the desktop. Thus, you should go to Finder > Preferences > General and make sure the 'External disks' option is ticked. Then you'll see the USB flash drive showing up on Mac desktop.

Fix 3. Change settings for Mac recognize an external hard disk in the Finder

Finder is the other access for us to check a connected external drive on Mac. If your flash drive or external hard drive is not showing up there, go to Finder > Preferences > Sidebar, and under Locations, you need to tick the option 'External disks'. By selecting this option, we can make sure that the connected external USB hard drive or flash drive will normally show up in the Finder.

Fix 4. Check the USB drive in System Information

When you cannot find the USB drive on the desktop or in the Finder, try to look for it in the System Information section, which is usually a hidden place for average Mac users.

Step 1. Go to Applications > Utilities > System Information.

Step 2. Check if the system detects the USB drive. Click 'USB' on the left panel, and you can also check the USB flash drive information.

Fix 5. Reset USB ports on Mac to detect a USB drive

Step 1. Restart Mac computer, press the Command +Option+P+R keys until the Apple logo appears.

Step 2. Press Command+Option+Esc keys to close all applications that are not responding.

Step 3. Plug the USB which is not showing up to your Mac computer. If it doesn't show up, click Apple icon and select 'Sleep'.

Step 4. Wake up the computer after a few seconds by pressing any key.

Step 5. Shut down the Mac, unplug the power cord, reattach it after 15 seconds.

If this doesn't work, we should suspect the corruption issue at this moment. Don't give up and try to do some repair by yourself.

Fix 6. Repair USB flash drive with First Aid if it doesn't show up

Step 1. Go to Applications > Utilities > Disk Utility.

1. Step 2. Select USB flash drive on the left panel of Disk Utility, and click 'First Aid' at the top toolbar and click 'Run'. Disk Utility will repair any errors on the drive automatically.

Step 3. Select the USB drive and click 'Unmount' at the top toolbar, unplug the USB and plug it back in 10-15 seconds.

Fix 7. Check and fix errors in a not recognized USB with Terminal

Step 1. Open Terminal in Utilities, type:diskutil list and press Return.

Step 2. Find the disk number of your USB flash drive, type: diskutil info disk2 and press Return. (Replace 2 with the disk number of your USB flash drive.)

Step 3. Type: diskutil eject disk 2 and press Return.

Step 4. Type: diskutil list and press Return.When the USB disappear from the Terminal list, close the window.

Step 5. Close Terminal and open Console to inspect your drive errors.

Step 6. Click 'Errors and Faults' to check if there are any errors.

Step 7. Reconnect your USB flash drive back to Mac, if no error shows up, your USB flash drive is safe.

Fix 8. Save data and reformat the not showing USB drive

Disk reformatting basically solves many hard drive issues, including the not showing up USB, particularly the time when you are able to see the USB icon but files are not showing. USB drive showing empty makes no sense, so you have to reformat the disk and make it usable again.

Note that reformatting will erase data. As long as the data matters, you need to follow the standard procedure to ensure zero data loss. [1] Download EaseUS Data Recovery Wizard for Mac, the professional Mac data recovery software, to perform a full USB drive data recovery. [2] Reformat the USB drive in Disk Utility.

To format the USB drive in Disk Utility:

Step 1. Go to Utilities and open Disk Utility.

Step 2. Select the not showing up USB flash drive in the Disk Utility sidebar.

Step 3. Click Erase on the top.

Step 4. Finish the necessary information (name, format, and scheme) to format the USB flash drive.

Fix 9. Update your macOS and firmware

Did your Mac's OS keep updating all the time? Chances are that your Mac won't recognize a USB drive, especially after a macOS update. This time, take a close look at the settings whether your Mac is up-to-date. Equally, firmware updates address a variety of hardware issues and the functionality of the USB ports could well be one of them. So, keep your software and firmware up to date will likely make the USB drive show up as normal again.

Mac Os Usb Disk Not Detected

Fix 10. Send the USB drive to a repair center

Nowadays even the branded USB flash drives are not expensive. If you've tried all the suggested troubleshooting methods, the USB drive is still not showing up on Mac, you have to accept the truth that it's severely damaged and beyond your ability to repair it.

Mac won't recognize a badly damaged flash drive or external hard drive since there is no way to show it up, even temporarily, which makes the data recovery difficult. The last chance for you to rescue data is to send the broken USB drive to a specialized data recovery service center nearby, and let the professionals try their best. You need to prepare for the manual data recovery cost, which is noticeably higher than the software data recovery. Hence, always try the cost-effective plan of using EaseUS Data Recovery Wizard to scan the USB drive for the first attempt.

Mac Os On Usb Stick

Step 1. Correctly connect your USB flash drive to your Mac. Launch EaseUS Data Recovery Wizard for Mac. Start selecting the flash drive and click Scan to let the software search lost files on it.

Step 2. After quick scan and deep scan, all files will be presented in the left pane in the scan results.

Install Mac Os From Flash Drive

Step 3. Select files you want to recover and click Recover Now button. Don't save the recoverable files to the USB drive itself in case of data overwriting.