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Before you start ​

Lost files are usually still on the drive until something overwrites them. These rules keep them there until DiskRescue has copied them off.

The rules ​

  1. Stop using the drive. Do not take more photos with the card, copy files onto it, or put it back in a camera or phone. Every write can overwrite deleted files.
  2. Do not let the computer "repair" or format it. Do not run chkdsk, fsck, "Repair disk" or "Format", even when the system offers to. They rewrite the structures recovery needs.
  3. Never save recovered files onto the drive you are rescuing. Use a different disk. DiskRescue refuses output on the source drive, also when it is reached through a partition, a link or another layer.
  4. Have enough free space on the other disk. A copy (image) of the drive needs as much space as the whole drive. Recovered files need as much as you expect back.
  5. Copy a failing drive first, then recover from the copy. A failing drive can get worse with every hour it runs. The copy is read once, carefully; everything else works from the image file.

DANGER

What can lose data: writing anything to the drive, formatting it, running a repair tool on it, and keeping a mechanically failing disk running longer than needed. DiskRescue itself only reads the drive.

When to stop and get help ​

Software cannot help in these cases, and every attempt can make things worse:

  • The drive shows a size of 0 bytes, or much less than it should.
  • A hard disk clicks continuously, beeps or does not spin up.
  • The drive smells burnt or got wet.

Power the drive off. A data recovery lab can often still get the files back. Never open a hard disk yourself.

What to expect by drive type ​

DriveWhat to know
SD card, USB pen drive"Card error" or "needs formatting" usually means the file list is damaged while the photos are intact. Do not format.
Hard disk with read errorsCopy it once, carefully. Stop if the noise gets worse.
SSDFiles that still exist on a failing SSD can be recovered. Deleted files have usually been erased by the drive already. Do not switch a failing SSD off and on more than necessary.

Unmount, do not eject ​

DiskRescue asks you to take a drive out of use before copying it, so nothing writes to it. In your file manager choose Unmount, not "Eject" or "Safely remove", which disconnect the drive.

Next steps ​