External hard drive not showing up? Safe checks — and the point of no return

Work out which of the three problems you have

Before opening a single menu, give the drive two quiet minutes of attention. Plug it in, watch the LED, rest a fingertip on the casing to feel whether the motor spins up, and listen. A drive that powers on silently and evenly is a different case from one that stays completely dead — and both are different again from one that has started making a sound it never used to. Those observations sort 'not showing up' into its three real categories: a connection fault (cheap), a file-system fault (fixable with care) and a hardware fault (one for the lab).

Hear clicking, buzzing, beeping, or a spin-up that keeps stalling and restarting? Go no further. That's mechanical trouble — typically crashed read/write heads or a seized motor, with dropped and knocked drives the classic cause. Left powered, a drive in that state can grind the very platters your files physically sit on. Disconnect it and skip straight to the final section.

The checks that cost nothing and risk nothing

Begin with the cable: the thin leads bundled with portable drives are a known weak point, and Seagate and WD units get through them at a remarkable rate. Move to a different port next — straight into the computer itself, never via a hub or front-panel socket — then to a second computer if one is handy. Mains-powered desktop drives add one more suspect, the power brick: a drive that won't spin at all may simply have a dead adapter, so test a compatible spare before condemning the disk.

On Windows, open Disk Management (right-click the Start button). A drive visible there but absent from File Explorer has often just dropped its drive letter — restoring one through 'Change Drive Letter and Paths' is harmless. But if the disk reports as RAW or 'unallocated', or Windows invites you to initialise it, the file system has corrupted. Your files are usually still present underneath — and initialising, formatting or letting Windows 'repair' anything writes directly over the structures a recovery is rebuilt from, so decline all three.

On a Mac, open Disk Utility and turn on View → Show All Devices. Seeing the hardware listed while its volume refuses to mount is common; the mistakes to avoid are Erase (destructive by definition) and running First Aid on a drive that sounds unwell, because repair passes push failing hardware hard. One benign case to rule out: a disk formatted for Windows won't mount properly on a Mac, and vice versa — the data is untouched, it just needs reading on the platform it was formatted for.

Two quirks of Seagate and WD portables

A Seagate portable whose LED lights while nothing appears on screen — and which sounds perfectly normal — very often has a failed USB bridge board or corrupted firmware. The data is generally fine; the route to it just isn't a new cable. With modern WD My Passport and Elements drives, skip the popular trick of freeing the disk from its enclosure altogether: the USB board encrypts everything in hardware, so the bare drive presents as scrambled nonsense in any other caddy. Proper recovery reads through, or works around, that original bridge.

Whatever the brand, end the plug-in-and-hope cycle. A drive that appears one time in five, then one time in ten, is tracing a failure curve — and every retry spends a little more of whatever life the hardware has left.

Where DIY ends and the free diagnostic begins

Draw the line here: any clicking, beeping or history of being dropped; a RAW or 'initialise' prompt over files you actually need; detection that comes and goes and is trending worse; or recovery software that has already churned for hours and produced nothing. Past that line, further experiments only spend the data — while establishing the real fault costs you nothing at all.

Wrap the bare drive in bubble wrap (keep the cables), post it tracked, and within 2 working days of it reaching the lab you'll have the diagnosis, a clear picture of what's recoverable and one fixed quote to accept or turn down. The external hard drive recovery page covers the service in full, or begin with the free online diagnostic.