Hardware Recovery and Techniques.

Recovery techniques

Recovering data from physically damaged hardware can involve multiple techniques. Some damage can be repaired by replacing parts in the hard disk. This alone may make the disk usable, but there may still be logical damage. A specialized disk-imaging procedure is used to recover every readable bit from the surface. Once this image is acquired and saved on a reliable medium, the image can be safely analyzed for logical damage and will possibly allow much of the original file system to be reconstructed.

Hardware repair

[[File:HD with toasty PCB.jpg|thumb|right|250px|Media that has suffered a catastrophic electronic failure requires data recovery in order to salvage its contents.]]

A common misconception is that a damaged [[printed circuit board]] (PCB) may be replaced during recovery procedures by an identical PCB from a healthy drive. While this may work in rare circumstances on hard drives manufactured before 2003, it will not work on newer hard drives. Each hard drive has what is called a System Area. This portion of the drive, which is not accessible to the end user, contains adaptive data that helps the drive operate within normal parameters.  One function of the System Area is to log defective sectors within the drive; essentially telling the hard drive where it can and cannot write data. The sector lists are also stored on various chips attached to the PCB, and they are unique to each hard drive. If the data on the PCB do not match what is stored on the platter, then the drive will not calibrate properly.[http://datarecoveryreport.com/#Swapping_PCB_Logic_Board Swapping PCB's on Data Recovery Report] In most cases the hard drive heads will click, because they are unable to find the data matching what is stored on the PCB.