HARD DRIVE DATA LOSS

Logical Recoveries

There are several ways one can experience data loss on a hard drive. The most common one is accidental deletion i.e. data was deleted that shouldn't have been deleted (yet). A variation of this is the accidental reformat, where a wrong drive or partition gets its table of contents wiped, so that it appears empty and can be repurposed.

Then of course there is file or file system corruption, typically caused when the OS crashes, or in worse cases, when malicious software (malware) was installed on a system and caused havoc and corrupted or deleted data. Under no circumstances should new data be written to the drive, otherwise data that needs to be recovered could be overwritten and therefore lost for good.

In terms of recovery, these situations are called logical recoveries, as the loss experienced is purely data related and independent of the medium the data is stored on. When such a situation has occurred, it is imperative to stop using the drive in question and either go back to a known good backup, or use data recovery to salvage the data that doesn't exist anywhere else.

Physical Failures

A different case of data loss (that is less common but much more severe) is when the drive starts to exhibit physical failures that prevent it from working correctly. Often these drive failures are accompanied by unusual sounds, like beeping, clicking or grinding noises. They might also exhibit unreliable behavior like disappearing and reappearing on the desktop for no apparent reason.

These recoveries are called physical recoveries, as the only way to get access to the data is to fix the physical problems first, before attempts can be made to recover the data. This typically requires a clean room environment and specialized hardware tools, in addition to the software tools needed to recover the data.