Fallen hard drive: what to do?

It still happens regularly with the external drives that they receive a blow or fall off the table.
We receive them here as regularly as clockwork.
Topped over on the table, dog passed by and stayed faltering on the cable, etc ...

If the drive is not spinning when this happens, the damage may not be so bad.
Don't forget that a hard drive is a wonderful piece of precision engineering.
The read heads float less than a micrometer above the magnetic layer.
If the disk spins while receiving an impact, the read heads can hit the magnetic layer and cause damage. A scratch of one millimeter easily covers hundreds or thousands of sectors.

If the disk continues to rotate, the magnetic particles released by the impact can end up between the read head and the magnetic layer, creating new scratches. which release particles, etc. This so-called avalanche effect can quickly destroy a hard drive completely.

What to do if the drive falls?

A fallen hard drive is can no longer be trusted.
If she clicks, discard it immediately, and if the data is valuable, take it to a data recovery specialist as soon as possible.

If she doesn't click, and if it is still accessible, copy the most important data to a new disk as quickly as possible.

We regularly receive disks, which the customer has sometimes kept clicking for hours in the hope that the disk would come back up. in Windows or Mac.
However, this is a vain hope.

When we open these drives, we often see a circle on the magnetic layer, or even worse.

For discs with scratches on one or more platters, we can in many cases still recover data from the other platters. However, this is only a partial recovery, and usually the file names are lost.
This is rarely done due to its complexity and cost, but for someone who has otherwise lost all their family photos, this is an alternative. Naturally, a good backup remains the best remedy.