Data recovery services: What is it and when will you make use of it?

Have you ever had a PC that just would not start up? Or a hard drive that is just not read by any machine?

Did an external hard drive stop responding, become unsearchable and/or start making funny clicking sounds?

Have you ever formatted a drive (albeit hard drive or flash drive (memory stick)), only to realise you needed the data on that drive and didn’t make a backup thereof before clicking on the OK button?

These are some of the scenarios wherein you could conceivably make use of data recovery services.

But what can data recovery services do for you, you may ask.

First off, please always bear on mind that while data recovery firms will always do everything in their power to recover your precious data, recovery is never 100% guaranteed, as there are circumstances that may make this impossible, e.g.

> drive struck by lightning or subject to continuous power surges;
> subjected to very strong magnetic fields;
> machine dropped or knocked over while the drives are working hard, where the disks are so badly damaged (surface scraped, disks bent or broken, spindle bent or snapped, read/write head penetrates the disks) that recovery effectively becomes impossible;

Data recovery is the process whereby data is recovered from a damaged or otherwise inaccessible drive.

there are two methods employed, viz.

> soft recovery, where recovery is possible by means of computer software;
> when soft recovery fails, one can perform hard recovery, where the hard drive is dismantled (in a Class 100 or less Clean Room) and, depending on the damage encountered, either replacing components within the hard drive where possible, or, as a last resort, the disks removed and placed in a specialised piece of equipment (a disk reader), which is then used to get the data from said disks (however, this is a labour intensive operation and is, as such, the more expensive option, with limited chance of success)

But what is the biggest causes of failure in hard drives?

> Severe viral infections, which may damage the boot sector, effectively rendering the drive inaccessible;
> Not performing regular cleanup and maintenance of hard drives (including, but not limited to, defragmentation (which can be scheduled on most operating systems), disk cleanup (removal of temporary files or unused / unusable files, to save space), or filling a drive beyond the recommended maximum of 75-80% of capacity (this additional space is what gets used for maintenance of said drive by the Operating System)
> Abuse of the drive, e.g. using a desktop / laptop drive as a server (with extremely high read and write activity, pushing the drive beyond its actual designed capabilities);
> moving the machine while the drives are spinning (refer below for an analogy of the workings of a hard drive and possible causes of damage)

Now, the question can be asked about how to avoid said issues.
To be honest, drive failure is inevitable, it happens to everyone at one time or another.
Yet there is a way to minimise the impact of the failure:

> Ensure you have an Uninteruptable Power Supply (with Surge Protection) connected between the power socket and your PC;
> Keep backups of your precious data, in a reliable storage (e.g. an External Hard Drive), not the drive on which your data is currently stored (remember to regularly check the quality of the backed up data). There are several modestly priced yet reliable backup tools available on the market;
> Do not manouver, move or shake your PC or Laptop while the hard drives are spinning (i.e. while it is on) – that includes walking around with the laptop on (if you need to do this, obtain a machine with Solid State Drives)

The promised analogy:

Consider the read / write heads of the hard drive as a Jumbo 747 Super.

Consider the palettes of the drive as the ground.

Now imagine the jumbo flying at Mach 5 three inches (approximately 75 mm) above the ground

On this scale,

> a wave of white light is approx 10 inches (~250 mm);

> a particle of smoke is a 1/2 metre diameter boulder;

> a fingerprint is a metre high wall;

> a dust particle is the size of a house;

impact with any of these is sure to cause damage.

However, the most frequest cause of hardware damage (i.e. physical damage to the disks and read / write heads) is movement. While the disks are spinning at full speed (between roughly 5400 rpm and 7200 rpm (or even more (up to approx 11.000 rpm) on the newer hard drives), depending on the make of the drive), any movement will cause the pallettes of the disk to wobble. On the scale used above, the wobble can be anything between 4 inches (~100 mm) and 8 inches (~200 mm), i.e. the palette will hit the read / write head, leaving bad sectors. Enough of these impacts will render the drive (and the read / write head) totally useless, with all data effectively lost.

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