External drive
not showing up on Mac?

Is this the only copy?

If a hard drive is grinding or repeatedly hard-clicking, stop using it and seek recovery advice. Seagate distinguishes abnormal sounds from normal activity and warns that continued use can damage platters. An SSD has no spinning mechanism; silence does not clear it of faults. Do not open, freeze, or run repair utilities on a damaged drive.

If it becomes readable and behaves normally, copy important files to another healthy device and open a few copies to verify them. If it disconnects, stalls, or makes abnormal sounds during copying, stop. When irreplaceable files have no backup, ask about data preservation before further testing.

Finder can hide a working disk

Click Finder in the Dock, then choose Finder → Settings → Sidebar and enable External disks. Expand Locations in the window’s sidebar. For a desktop icon, select External disks under General too. If the sidebar itself is hidden, choose View → Show Sidebar.

Apple documents these display controls. On macOS Monterey 12 and earlier, the menu is Finder → Preferences. If the volume opens now, visibility explains the missing icon; check the files and backup rather than replacing hardware.

Test one connection at a time

For an undamaged drive, use its supplied or a known-working compatible data cable. Connect directly to the Mac where possible, bypassing a hub or dock; otherwise use an adapter supported by the drive’s maker. Try another Mac port, then another compatible cable. Use only the correct power supply if the drive requires one.

On a Mac laptop with Apple silicon, unlock the Mac and approve your trusted drive’s accessory prompt. If you previously chose Don’t Allow, reconnect it while unlocked. Apple says power can still flow when data access is denied; a light is not proof of access. Ask the administrator if a work or school Mac restricts accessories.

Before disconnecting a mounted drive, close its files and eject it in Finder. If macOS cannot eject it, close apps, save work, and shut down before unplugging. Avoid repeated unplugging during reads or writes.

Look beyond the missing icon

Open Applications → Utilities → Disk Utility, then View → Show All Devices. Expand the arrow beside the external device. Match its name and capacity; leave the Mac’s internal storage alone. Apple’s full-device view separates the physical device from containers and volumes.

Volume appears gray or unmounted

Select that volume and click Mount once, following Apple’s mounting instructions. If encrypted, use its correct unlock method and password. Do not erase it because you lack the password.

Volume mounts and opens

Return to Finder and copy needed files elsewhere. Mounting restores availability; it does not certify the drive’s health.

Only the physical device appears, or Mount fails

Record the exact message and stop before formatting. Missing volumes can involve disk structure, format, or a locked device; this is not a diagnosis of a failed part.

Absent here does not name the broken part

For a safe drive still absent from Disk Utility, hold Option while opening the Apple menu and choose System Information. Under Hardware, select USB or the applicable Thunderbolt entry and look for the drive or enclosure.

Appearing here shows that something on the connection is detected; it does not prove the stored files are readable. If absent, one comparison with another trusted, compatible Mac can help. A drive working there points toward the first Mac’s connection or configuration. Failure on both still needs assessment. Record the result; avoid a loop of resets or cable changes.

First Aid starts with a backup

Apple calls for a current backup before Disk Utility repair. If you cannot back up the only copy of needed files, stop and seek recovery advice. First Aid repairs disk structures; treat it as a change to the drive.

Send the observations with the drive

Contact the drive maker or ask HDR about assessment for persistent absence, failed mounting, repeat disconnections, physical damage, or repair failure. If files are irreplaceable, say so first; a specialist recovery lab may be appropriate. A warranty replacement is not a file-recovery plan.

Include the Mac model and macOS version from About This Mac, drive model, cable/dock/power setup, exact error, Disk Utility and System Information results, and backup status. Bring the drive and its cable/power supply. Crop private names from screenshots; do not send passwords.