FixAudio, Displays and Accessories

External hard drive not showing up

Your external hard drive or flash drive does not appear in File Explorer or Finder. Check power, cables, drive letters and format, and avoid erasing it by mistake.

  • Updated
  • 12 min
  • Intermediate
Applies to
  • Windows 11
  • Windows 10
  • Mac

Rate this guide

An external hard drive, SSD or flash drive does not appear in File Explorer or Finder after you plug it in. Find out whether the problem is power, the cable, a missing drive letter, or a format your computer cannot read, without putting your files at risk.

Windows 10 no longer gets free security updates

Support for Windows 10 ended on October 14, 2025, apart from an extended program you must enroll in. The steps still apply, but plan to move to a supported system.

Before you start

Treat the files on the drive as precious until you know otherwise. Several screens in this guide offer to Format, Initialize or Erase the drive. Those actions delete everything on it. Do not accept them for a drive that holds files you want.

Have the drive's own cable and, if it came with one, its power adapter.

From simple checks to Disk ManagementA top-to-bottom flow chart with 8 boxes. Work through them in order and stop when the problem is fixed. The full text follows the picture.From simple checks to DiskManagementNoNo1Check the cable, powerand drive light2Try another port, no hub3Does the drive appear?Yes: You are done4Look in DiskManagement or DiskUtility5Is it listed but has no letter oris not mounted?Yes: Give it a letter or mount it6Check the drive format7Test on another computerNot seen anywhere? Do notformat it. Ask a datarecovery service.
Stop as soon as the drive appears.
Text version of this diagram
  1. Step 1: Check the cable, power and drive light
  2. Step 2: Try another port, no hub
  3. Question 3: Does the drive appear? If yes: You are done. If no, go on to the next item.
  4. Step 4: Look in Disk Management or Disk Utility
  5. Question 5: Is it listed but has no letter or is not mounted? If yes: Give it a letter or mount it. If no, go on to the next item.
  6. Step 6: Check the drive format
  7. Step 7: Test on another computer
  8. If nothing worked: Not seen anywhere? Do not format it. Ask a data recovery service.

Try these fixes in order

1. Check power and cables (2 minutes)

  1. Look for a light on the drive. A light that comes on, or a drive you can hear spinning, means it has power.
  2. If the drive has its own power adapter (common for larger desktop drives), plug it in and switch it on.
  3. Check both ends of the cable are firmly seated. Try a different cable.
  4. Plug the drive straight into the computer. Microsoft notes that a non-powered hub may not supply enough power for a drive, and Apple advises plugging a self-powered hub into its power adapter or connecting directly.
  5. Try a different USB port. On a desktop, use a port on the back of the case.

If none of the above works, see also USB device not recognized.

Stop if the drive clicks or grinds

If a hard drive makes repeated clicking or grinding sounds, unplug it and stop trying. Repeated attempts can make damage worse. Ask a professional data recovery service about the files.

2. Look in Disk Management (Windows)

Disk Management shows every drive Windows can see, even those without a drive letter.

  1. Right-click the Start button and select Disk Management.
  2. Find your drive in the list at the bottom. Match it by its size, which should be close to the size on the drive's label.
  3. Read what it shows next to the drive.
What Disk Management may show and what it means
What you seeWhat it meansWhat to do
Drive listed, healthy, no drive letterWindows sees it but has not given it a letterAssign a letter (next section)
Drive listed as OfflineThe disk is switched offRight-click the gray disk label on the left and select Online
Not Initialized or UnallocatedWindows finds no usable layoutRead the stop note below before doing anything
Space shown as RAW or an unknown partitionThe format is unknown to Windows, for example a Mac formatDo not format. Read the format section
Drive not listed at allWindows does not detect the driveReturn to power and cables, then test another computer

3. Give the drive a letter

  1. In Disk Management, right-click the volume of your drive (the box with the size and a status such as Healthy).
  2. Select Change Drive Letter and Paths.
  3. Select Add (or Change if it already has one).
  4. Select Assign the following drive letter, pick a letter from the list, and select OK.
  5. Open File Explorer, then This PC. The drive should appear with the letter.

If Change Drive Letter and Paths is gray

Microsoft says this means the volume is not ready: the disk may be unallocated and need initializing, it may be a hidden system or recovery partition, or you may lack permission. Sign in with an administrator account. Never change the letter of the drive that holds Windows.

Initializing or formatting erases the drive

Only choose Initialize Disk, New Simple Volume or Format if the drive is new or you have confirmed it holds nothing you need. If it holds files, copy them somewhere else first if the drive opens at all, or leave it alone and ask a data recovery service. Check the disk number and size before every choice, so you do not pick your internal drive by mistake.

4. Check the drive format

A drive formatted for one system may not be readable on another. A drive that works on a Mac may look empty or unreadable on Windows, and the reverse.

Which systems can use common drive formats
FormatWindowsMac
exFATRead and writeRead and write
FAT32Read and writeRead and write
NTFSRead and writeRead only by default
APFS or Mac OS ExtendedNot readable without extra softwareRead and write

A drive that is encrypted (BitLocker on Windows, or an encrypted volume on a Mac) asks for a password or recovery key first. Enter it; do not format the drive because it asks.

If Windows offers You need to format the disk before you can use it, select Cancel. Plug the drive into a Mac to copy the files, or ask the drive maker about Windows support. To use one drive on both systems later, exFAT is the usual choice, but you must copy the files off first, because changing the format erases the drive.

5. If the drive is missing on a Mac

  1. Open Finder. Look under Locations in the sidebar for the drive.
  2. If you expect it on the desktop, choose Finder > Settings (earlier macOS: Preferences), open the General tab, and tick External disks. Then open the Sidebar tab and tick it there too.
  3. Open Disk Utility (in Applications > Utilities). Choose View > Show All Devices. If the drive is listed but grayed out, select it and use Mount. If it will not mount, copy off any files you can reach first, then select the drive and choose First Aid. First Aid checks the drive and may change it while repairing.
  4. Hold Option and choose Apple menu > System Information. Under USB or Thunderbolt, check the drive is listed. If it is not, the Mac cannot see it, so check the cable and power again.
  5. On a MacBook with Apple silicon, check System Settings then Privacy & Security then Accessories, and allow the accessory if an earlier alert was declined.

Do not choose Erase

In Disk Utility, Erase deletes the drive. Use it only for a drive you have decided to wipe.

6. Reinstall the drive's driver (Windows)

  1. Right-click Start and select Device Manager. Expand Disk drives.
  2. Right-click the entry for your external drive and select Uninstall device. This does not erase the files on the drive.
  3. Unplug the drive, wait a minute, then plug it back in. Windows installs the driver again by itself.

If it still does not work

  • Test the drive and cable on another computer. If it fails there too, the drive or its enclosure may have failed.
  • If the files matter, stop and ask a professional data recovery service. Do not run repair or format tools first.
  • Once you have your files back, protect them. See backing up your files or Time Machine on a Mac.

Frequently asked questions

Why does my drive show in Disk Management but not in File Explorer?

It usually has no drive letter or is offline. Add a letter or set it online as described above.

Is it safe to unplug a drive without ejecting?

Not always. Eject first, using the Safely Remove Hardware and Eject Media icon in Windows or the eject button in Finder. Unplugging during a write can damage files.

Should I use the repair button if Windows offers to scan and fix the drive?

Copy the files first if you can. A repair can change the drive, so a backup copy keeps you safe.

Was this guide helpful?

Choose from 1 star (not helpful) to 5 stars (very helpful)

Rating this guide needs JavaScript. You can send feedback on the contact page instead.

Official resources used

Pages consulted while preparing this guide. Check them for the latest details.

Need more help?

If this guide did not solve your problem, send us a message and tell us what you tried.

Contact us

Beware of fake support

Real support never asks you to call an unfamiliar number, pay with gift cards or let a stranger control your computer.

Read how to stay safe online