Why Does Freezing a Hard Drive Give It Life

[Ranayna]

ddrescue will do a sector based copy of the whole drive. That will include space marked as free, and therefore potential recoverable files, or parts of them.

That is a reason why ddrescue (or similar) should always be the first step in datarecovery.

[Kasper]

No, you were exactly right. It is mechanical, not electronic. It’s got nothing to do with solder joints. The effect in question is (erroneously!) called “stiction”, but it’s actually lubricant failure. Freezing causes tolerances to change just enough to allow the platter to spin up.

Sorry, totally wrong. It’s lubricant failure in the platter bearings. Nothing to do with electronics failure.

the drive spins

What I'm still trying to figure out is how tooki knew without a shadow of doubt that lubricant failure was the cause. 

[bostonman]

What I'm still trying to figure out is how tooki knew without a shadow of doubt that lubricant failure was the cause.

I'm curious too.

If the bearings are failing, why is the drive losing files?

[BradC]

If the bearings are failing, why is the drive losing files?

If the "drive is losing files" because they are becoming unreadable (I/O error) then it's potentially mechanical or media related.

If it's "losing files" as in "they were in the directory yesterday and now they're not" then something on the system the drive is plugged into is deleting them. Sectors are either readable or they are not. The bits don't magically change in a consistent and undetectable manner.