Ordinarily when you plug in an external difficult bulldoze to your Mac's USB port you lot volition see information technology announced on the desktop (aka mountain on the desktop). You can also see it in the Finder in the left cavalcade under Locations (or Devices on older versions of macOS). If the drive is non showing up on your Mac chances are it has not been formatted correctly, has been corrupted, or is faulty.

We testify you how to work out whether the reason the external drive is not mounting on your Mac up is due to a problem with the drive itself, the cable or the port, and how to resolve the trouble and access data on your drive.

This commodity assumes you lot accept an external drive that connects to your Mac via the USB-A, USB-C, or a Thunderbolt port. If you have a NAS drive that connects over the network then yous should read this article about connecting to a NAS drive.

How to fix a drive that won't bear witness upward on a Mac

There are a number of reasons why your difficult drive, flash drive, USB bulldoze, or SSD might not be showing upwards. It may have been formatted incorrectly, it may exist corrupted, information technology may take a faulty (or inadequate) cable, or there could be something else.

If yous run though the following steps you should hopefully be able to identify the crusade and fix the trouble that is stopping your external drive from opening on your Mac.

1: Edit your preferences

Hopefully there is a really piece of cake ready to get the difficult bulldoze to mountain on your desktop. Try the following to make certain your Mac is set to testify mounted drives on the desktop.

  1. Open the Finder.
  2. Click on Finder in the menu at the tiptop of your screen.
  3. Cull Preferences > General and make sure that there is a tick abreast External Drives.finder mount drive

If information technology was already fix so that the external drive would appear on the desktop then continue to follow the steps beneath.

2: Check the cable

The first port of call is always to check that it's plugged in, but we are sure y'all take done that. The problem might be with the cablevision though.

One of the main reasons why drives fail to mountain is if the bulldoze isn't receiving enough power. If the bulldoze is powered via a USB-A cable you need to bank check that adequate power is being delivered to the drive. Very onetime Macs may require a USB ability cable, a cable that splits into two USB connectors that need to both be plugged into your Mac, in guild to deliver enough power to the bulldoze. Similarly, brand sure that the drive doesn't take an external power supply it should be using.

On the field of study of cables, make sure that it'due south not at fault. Try using a different cablevision with the drive to run into if that fixes the problem. Similarly, if you are using a USB port via a hub check that's non what'southward causing the problem.

Also bank check that the port on your Mac isn't the trouble. Try plugging into a different port. Or if you lot simply have the one, plug another device in and see if that works ok.

3: Attempt another Mac and so try a PC

The next step is to try plugging the drive into another Mac. If it also fails to mount there you volition know that there is a problem with the drive while if it does mountain then the problem is with your Mac.

The next stride is to try plugging the drive into a PC. If the drive mounts on the PC it's likely that you have discovered what the problem is: the drive is formatted for PCs and can't be read by your Mac.

4: Use Disk Utility to access the drive

If the diverse checks above suggest that the deejay is faulty then you tin can use Apple's Disk Utility programme to access the disk and potentially fix any is causing the effect. Here'due south what to do:

  1. Find Disk Utility by opening Spotlight (cmd+Infinite-bar) and offset typing Deejay Utility, press enter to open the programme.
  2. Await in the cavalcade on the left to see if the hard drive appears there.
  3. If you can run across the hard drive in Disk Utility cheque underneath information technology for a volume. If it is there click on information technology and select Mount. If your Mac has already mounted the drive the option Unmount will be displayed instead. (If in that location is no volume listed your Mac is non able to admission the drive. The Mount pick will be greyed out.)Disk Utility Mount Hard Drive
  4. Your options are Beginning Aid, Erase and Restore. First Assistance will bank check the disk for errors and and then repair the disk if necessary and this is the option to choose. (Restore allows you to erase the contents of the bulldoze and supersede that with data from somewhere else. Erase deletes all the data stored on the drive. If you need the data on the drive do not choose Erase or Restore!)
  5. Click the First Assist tab and select Run.Run First Aid Mac
  6. If after running First Aid the Mac finds errors you could ready you may see the choice to Repair Disk. If you do, go ahead and run the repairs.

5: Alter the drive format

If your Mac is unable to repair the disk if is probable that the bulldoze is either formatted using a file system that the Mac cannot read, or information technology is well and truly broken - if it's the latter nosotros propose you follow this tutorial near recovering data from a damaged disk.

Hopefully though the drive is fine only the format is wrong. Hither'due south a fleck of background on file formats:

  • Windows PCs use NTFS file format.
  • Mac computers, prior to Sierra, used the HFS+ file format.
  • In Loftier Sierra Apple introduced a new file system called Apple File Organization (APFS).
  • exFAT or the older FAT32 are formats that can be read by Window and Mac computers.

To make sure your drive tin can be read past Macs and PCs you need to format it using exFAT or the older FAT32. We'll explain how to do that below.

It is possible that the difficult drive has been formatted using a different file system (i.e. on a Windows PC). In that example, if you need to access the data on the drive you'll demand to connect your drive to a Windows PC that does recognise it and re-create the data before moving on to the adjacent footstep.

Having got the data of the drive via a PC you lot can reformat the bulldoze so that you can add the data again. Here'southward how to reformat your drive so it tin exist read by and Mac or a PC.

  1. Open Disk Utility (equally per the steps above).
  2. If you don't require the information on the hard drive, select the deejay and click Erase.
  3. Before Disk Utility starts to erase the disk it volition pick a format for you. You lot tin change this if you click on the Formatting options. Choose your format, probably exFAT if you want to brand sure it'due south compatible with PC and Mac, otherwise, Mac Os Extended (Journaled) is probably the best option.Drive formats Mac and PC
  4. Give the drive a name.Name drive
  5. Click on Erase and wait for your Mac to erase and and so reformat the bulldoze.

6: Try a data recovery app

If y'all accept been unable to access the information on the drive then you lot might want to endeavour one of the options included in our round up of the Best data recovery apps for Macs.

Our recommendations include EaseUS Data Recovery for Mac, £95.99/$89.95 at Easeus, Stellar Data Recovery for Mac, £43.99/$59.99 at Stellar, or Recoverit £69/$79.99 at Wondershare.

7: Always disconnect your drive properly

We have final proffer to make that is more than of a baby-sit against this mistake happening again.

Make sure that your external drive doesn't go damaged in the futurity by always unmounting the deejay properly after using it. Don't just unplug the USB cable. To unmount your drive you tin right-click (command-click) on the icon on the Desktop or in the Finder and cull Eject. Apparently most drive issues are caused when the disk is removed without ejecting it properly.

Decided there is no hope for your faulty difficult drive, we have a circular up of some of the best we've seen here: The best Mac hard drives.