When you plug an external drive into your Mac, it should instantly appear not only on your Mac’s desktop but in the Finder app too. But what if your external drive doesn’t appear when plugged into your Mac? Is it time to buy a replacement?
Possibly, but there are a few easy fixes that you could try before parting with your hard-earned cash. After all, it could be a relatively simple issue, like the use of an incompatible file format or a faulty cable, that is easy to fix.
We walk you through how to fix an external drive that won’t appear on your Mac right here.
Check the cable
We’re sure you’ve already made sure that the external drive is plugged in, but have you checked the cable? One of the main reasons why external drives don’t mount is lack of power. If the external drive uses the older USB-A cable, you should check whether there’s enough power being delivered to the drive – especially when using older Macs with less USB power on offer. If there’s a cable with two USB ports at the end, make sure you plug both in – not just one.
It’s probably also worth making sure that the external drive doesn’t require an external power supply to function. Most modern external drives are powered entirely via USB, but some older drives require a separate power supply.
Edit your preferences
There’s always a chance, albeit slim, that your external drive is connected but isn’t displaying in the Finder app. It’s enabled by default on most Macs, so you will have had to have turned it off yourself in the past, but it’s always worth double-checking before moving onto more complex fixes.
Open the Finder app.
Click Finder in the menu bar.
In the General tab, make sure there’s a tick in the External disks box.
If this was already enabled, it’s time to move on to our next fix.
Try another Mac, and then a PC
There might be an issue with your Mac, so we’d recommend trying to access the external drive on another Mac if possible. If it successfully mounts with the other Mac, you know it’s a problem with your Mac specifically – possibly the port you used to connect the drive. But, if it’s still unmountable on another Mac, the problem could be the file format.
To confirm whether this is the case, try accessing the external drive from a Windows PC. If it works, then you know what you need to do: reformat the external hard drive. We cover that in more detail below.
Repair the drive
If your external drive isn’t recognised on any Mac or PC, chances are there might be digital damage. This could make the disk unreadable, but depending on the level of corruption, you might be able to use Apple’s Disk Utility to try and repair it.
Open the Disk Utility app. The easiest way to do this is to access Spotlight (Command + Spacebar) and search for Disk Utility.
Select the external drive from the list of external drives on the left-hand side of the app. If it doesn’t appear here, you’ll have to try another one of our fixes.
Click Mount if your Mac hasn’t already mounted the drive.
Once mounted, click the First Aid icon – this checks the drive for errors and tries to repair it if necessary.
If Disk Utility finds any errors, you’ll be alerted and prompted to run Disk Repair.
Once repaired, you should be able to access your external drive as normal.
Change the drive format
If your external drive appears when plugged into a PC but not your Mac, chances are that the drive’s formatting isn’t compatible with macOS. For those unfamiliar with data formats, there are several popular options:
NTFS: Default file format for Windows PCs, not compatible with Mac.
Mac OS Extended: Pre-Sierra file format for Mac, not compatible with PC.
APFS: File format introduced in macOS Sierra, not compatible with PC.
FAT/FAT32: Older file format limited to a maximum 4GB file size, but compatible with PC, Mac and Linux.
ExFAT: Upgraded version of FAT32 without file limits, compatible with PC, Mac and Linux.
Chances are that if your drive is recognised on PC but not Mac, it uses the NTFS file format. The good news is that it’s easy to change the format – the bad news is that doing so will completely wipe the drive, deleting any previously-stored data. We’d recommend using a PC to transfer files prior to reformatting the drive for use with Mac where possible.
When you’re ready to reformat the drive, follow these steps:
Plug your external drive into your Mac.
Open Disk Utility.
Select the external drive from the list on the left.
Enter a new drive name and select the new format. If you want to use the drive across PC and Mac, we’d recommend ExFAT, but if you’re on macOS exclusively, we recommend Mac OS Extended (Journaled). Only fast external SSDs can utilise APFS formatting.
Click Erase to confirm and start the reformatting process.
We cover the process of reformatting an external drive for Mac in more detail separately.
Use a data recovery app
If all else fails, you’ve always got the option of using a third-party data recovery app. These are generally paid apps, but they could restore your external drive depending on the issue. There are too many to cover here, but our sister site Macworld UK outlines the best data recovery apps for those interested.
Top tip: Disconnect your drive safely
While this won’t help you in your current predicament, there is a simple bit of advice you can follow to help avoid data corruption: always disconnect your drive safely. Whatever you do, don’t unplug the USB cable willy-nilly.
Instead, properly unmount your drive before disconnecting. This can be done by right-clicking the drive icon on your desktop and clicking Eject, or by clicking the eject icon next to the drive in the Finder app.
If you’ve tried everything and still can’t get your external drive to connect, we’ve got a roundup of the best external drives to help you find the perfect replacement.
For more top Mac tips, here’s how to use emoji on Mac, and how to use an iPad as a second screen on Mac.