Data recovery is the process or retrieving lost, formatted, corrupted or damaged data. Data recovery happens when users cannot access their data in a normal way.

The data is usually recovered from storage media like external or internal hard disk drives, USB flash drives, solid-state drives (SSDs), RAID subsystems, DVDs, CDs, magnetic tapes or other electronic devices.

In other times, data recovery can be necessitated by physical damage to the storage devices or logical damage to the file system, which can prevent the host operating system from accessing it.

Phases of data recovery

There are four phases of a successful data recovery. However, this can vary depending on the type of data damage and the recovery process required.

Phase 1

Repair the hard disk drive

Here, the hard drive is required to be prepared so that it can start running in one way or another, or at least be in a state in which the data can be read again.

Phase 2

Image the drive to a new drive or disk image file

When a hard disk drive fails, the top priority is usually figuring out how to retrieve the data off the drive. If the drive is used for long in its faulty state, it increases the probability of permanent damage to the data. Creating an image of the drive creates a secondary copy of the data on another device. Here, testing and recovery processes can be done without harming the source.

Phase 3

Logical recovery of files, MBR, partition and file system structures

After the drive has been duplicated to a new drive, an attempt can be made to retrieve the lost data. There are reasons why a drive can fail logically. Using the duplicate, it can be possible to repair the partition table or MBR. This allows the file system’s data structure to be read in order to retrieve the lost data.

Phase 4

Repair damaged files that were retrieved

Data can be damaged if files written on a particular sector in the hard drive have been damaged. These files can be recovered using various recovery software programs or using a hex editor to manually reconstruct the files.