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uk Technology & digital loss external hard drive not mounting • hard drive won’t mount • drive not recognised • drive not showing up • usb drive not detected • disk not mounting mac • disk not mounting windows • external drive clicks beeps • drive asks to format • drive says uninitialized • disk appears but no files • important files on drive • photos documents lost panic • sudden storage failure • data recovery first steps • stop using the drive now • accidental data loss • corrupted file system fear

What to do if…
your external hard drive suddenly will not mount and important files are on it

Short answer

Stop trying random “fixes” and stop writing to the drive. Safest first move is to disconnect it, keep it powered off, and switch to “copy out / recover” thinking (not “repair / reformat”).

Do not do these things

  • Don’t click Format, Initialize, or Erase just to “make it show up”.
  • Don’t run repeated repair tools in a panic (especially anything that says it will fix errors), if the files matter.
  • Don’t keep unplugging/replugging rapidly or swapping power/cables repeatedly if the drive is making unusual sounds (clicking, grinding, beeping).
  • Don’t install “miracle recovery” apps from pop-ups or ads you found mid-panic.
  • Don’t open the drive enclosure or take the casing apart.

What to do now

  1. Freeze the situation (prevent overwriting).
    Safely eject (if possible), then unplug the drive. If it has its own power supply, turn it off. Put it somewhere it won’t get knocked or overheated.

  2. Write down what happened (you’ll forget details).
    Note: when it last worked, what you were doing (copying files? moving it?), any messages (“needs formatting”, “unreadable”), whether it spins up, and any new noises.

  3. Do one low-risk check for a simple connection problem.
    Try once with: a different USB port, a different cable, and (if it has one) the original power adaptor. Avoid repeated tries—especially if the drive is behaving oddly.

  4. Check whether the computer can “see” it without changing anything.

    • Windows: open Disk Management and see if the disk appears (even if it has no drive letter). Do not choose options like Initialize or Format.
    • Mac: open Disk Utility and see if the device appears in the sidebar. Do not choose Erase.
      If it appears but says “uninitialised”/“not mounted”/“unknown”, treat this as a recovery situation, not a formatting situation.

  5. If the drive appears and you can access any folders: copy the most irreplaceable files first.
    Copy small, critical items (photos, documents) to a different drive or cloud storage. Don’t “move” (which deletes originals). If copying is extremely slow or errors start, stop and move to the next step.

  6. If you can’t access files (or the drive makes clicking/grinding noises): stop DIY and consider professional data recovery.
    Professional recovery is expensive, but repeated DIY attempts can reduce the chance of success. Keep the drive powered off until you decide.

  7. If the drive is new or recently purchased: protect your consumer position without sacrificing your data.
    If you may return/repair it, do not send it back until you’re sure you can live without the data (returns often mean the device is wiped or replaced). Contact the retailer/manufacturer and ask what their process does with stored data.

  8. UK-specific support if you’re stuck dealing with a retailer/manufacturer.
    If you’re getting nowhere, you can contact the Citizens Advice consumer service for guidance on next steps and escalation options.

What can wait

  • You do not need to decide today whether to buy a new drive, change your backup setup, or “upgrade” to a NAS.
  • You do not need to run deep scans, command-line repairs, or reformat “just to test”.
  • You do not need to organise all files—focus only on preserving what you can.

Important reassurance

This is a very common failure mode, and panicky “repair” clicks are one of the main ways people accidentally make recovery harder. Pausing, powering down, and switching to careful retrieval is the right instinct.

Scope note

This is first-step guidance to prevent avoidable loss and buy time. If the data is high-value (legal, business-critical, irreplaceable photos), a specialist recovery service is often the safest path.

Important note

This is general information, not professional advice. Storage failures can have multiple causes, and some tools can change data on the disk. When files are important, prioritise non-destructive steps and consider a qualified technician or data-recovery specialist.

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