Recovering Data from a Hard Disk Drive

Whatever has happened to your hard drive, the recovery process we use is data-safe. We will always create a clone of the hard disk before attempting recovery, this way it is always possible for us to return the drive to you in the same state as we received it. There will be some cases where a drive deteriorates whilst imaging but the processes we use will minimise this risk. All work is carried out in-house and we have a monitored Class 100 clean air environment for all work where the drive has to be opened. Most manufacturers will honour any remaining warranty should we need to open a drive.

With modern hard disks recovering data has become a more technical challenge than earlier models. The failure modes though have not changed and remain as follows

  • Logical Problems on Hard Disk
    Recovering deleted files, formatted drives, virus damaged data. These may seem simple problems and indeed the process for recovery is straightforward, however regaining access can be difficult, especially on some modern systems such as EXT, HFS+, encrypted files, etc.

  • Hard Disk Firmware Problems
    Hard disk drives contain an area or zone that is not accessible by the user. inside this area the manufacturer stores information that is required to make the drive function at it's best. Typically the firmware is stored as 'modules' for example, SMART modules or defect mapping and translator, adaptive parameters and a whole range of overlays, tables and modules all designed to keep your drive running at optimum performance. However, when a firmware module becomes corrupt, or develops a bad sector the drive will behave erratically, the drive runs slow or not even start up at all.
     
  • Electronics Problems on Hard Disks
    On the back of a hard disk is the electronics board and is basically a mini computer in its own right. If this fails, then the hard drive can show a range of symptoms from a completely dead hard drive to clicking noises. With modern drives, it is not usually possible to swap over an electronic circuit board from another drive as modern drives tend to be fine tuned at the factory and will contain unique 'adaptive' parameters that means a PCB swap may not work. Modern Seagate, Toshiba, Hitachi, Western Digital and some Samsung drives can not have direct board swaps.

  • Hard Disk Read/Write Heads
    In order for a drive to read and write data, 'Giant Magneto Resistive' (GMR) heads are used these are attached to an internal electronics assembly - the head preamplifier circuit. When this circuit fails then the heads are unable to read the data on the drive correctly, and the most common symptom is the heads clicking as the drive searches for the servo. The only method of repair is to replace the entire head stack assembly.

    Also, when the physical heads fail they can cause damage to platters - this is a more serious problem.

    Hard Disk Motor Problems
    The most common problems with hard disk motors are worn bearings resulting with loud rattling noises or a completely seized motor. Both these problems require a complete strip-down of the drive including removal of platters, heads and all other internal components and either replacing the motor assembly or transferring the platters to a good shell.

    Where there is more than a single platter involved, then vertical alignment is critical - if this alignment is lost, then it would be extremely difficult if not impossible to re-align. Even a few years ago, a recovery of this type would not have been attempted by other companies, however we have researched this aspect of data recovery exhaustively and have had special fixtures made that enable us to maintain this alignment and have completed hundreds of platter swaps over the years.

For internal examination and work we have our own Class 100 clean air systems that are used for data recovery. For more information please contact us on 0800 072 3282 or through our contact page linked above.


 

Testimonial

"The response from MjM was outstanding a top quality firm."
Gareth Pritchard, HP