How do I get files off a computer that will not start?

A computer that will not start is usually a power, display or system fault rather than a dead disk, and the files are sitting there intact. The order matters: everything you do that writes to the drive reduces what can be recovered if it does turn out to be failing.

Safety

Step by step

1. Rule out the simple causes first.Different power lead, different socket, battery removed and mains only, external display, and a long press on the power button to force a full shutdown. A machine that seems dead is frequently a charger or a stuck power state.
2. Listen to the drive.If there is any clicking, grinding or repeated spin-up-and-stop, stop immediately. That is mechanical failure and each attempt makes recovery harder. Decide there whether the data justifies a professional service.
3. Work out whether it is the machine or the drive.If it powers on and reaches a manufacturer logo or a diagnostic screen, the hardware is largely working and the problem is the system or the drive's contents — which is the recoverable case.
4. Try booting from a USB stick.A Linux live USB made on another computer boots without touching the internal drive and lets you browse it and copy files to an external drive. It is free, it changes nothing, and it works on most machines.
5. Use the recovery mode on a Mac.Recovery mode gives access to Disk Utility and Terminal, and target disk mode or share disk lets another Mac see the drive directly over a cable. That is the simplest route on Apple hardware.
6. Remove the drive and use an enclosure.For most laptops with a removable drive, an inexpensive USB enclosure or adapter turns it into an external drive readable on any computer. Check whether your model has a soldered drive first.
7. Copy the important things first.Documents, photos, desktop, downloads. Not a full disk image. If the drive is marginal it may fail partway through, so take what matters most at the start.
8. Never write to the failing drive.Do not install software on it, do not run repairs on it, and do not save recovered files back to it. Recovery tools go on another machine and output to a different drive.
9. Deal with encryption before you need to.A BitLocker or FileVault encrypted drive is unreadable in another machine without the recovery key. Find the key — it is usually in your Microsoft or Apple account — before removing the drive.
10. Try recovery software only after imaging.If files are deleted or the file system is damaged, make a full image of the drive first and run recovery tools against the image. Working on the original drive risks making things worse.
11. Know when to stop.A mechanically failing drive with irreplaceable data is a professional job. Recovery services are expensive, and repeated home attempts are the main reason they fail.
12. Set up a backup once the files are safe.This episode is the argument. Whatever you have just recovered should exist in two places from now on.

Tips

• Making the Linux live USB is the hardest part and it takes twenty minutes on any working computer. Everything after that is dragging files between folders.
• If the machine is under warranty, ask about repair before opening it — many manufacturers will not return the drive, so recover the data first either way.
• A drive that mounts but is very slow is often failing. Copy the most important things first, not alphabetically.

Common mistakes

• Reinstalling the operating system to fix it — That writes over exactly the space deleted or damaged files occupy, and it is usually irreversible. Recover the data before any repair.
• Repeatedly powering up a clicking drive — Each attempt causes more physical damage and reduces what a recovery service can retrieve. Stop at the first click.

If it doesn't work

Questions people ask