Recovering Data From a Corrupted Hard Drive

There is a reason for most people who know computer hardware to say "Yeah, your hard drive is dead." as though it happens everyday. Because it does happen everyday. Brand new and very old ones are the most common to get damaged. Either way, data is always important and needs to be kept safe from any disaster, seen or unseen.

There are basically two modes of data corruption: logical failure and mechanical failure. The former means your data is messed up, while the latter means there is physical damage to your hard drive. Either type can happen in many ways, ranging from mild and easy to recover, to recycling your drive for scrap. Few of the most common causes are given here.

The process can be as easy as getting a scratch on your own skin. It's magnetic media, so any other strong-enough magnetic force can distort the data stored on the hard drive. Even moving the hard drive (especially when in use) can cause the internal components to touch the disk, scratching it.

Another problem could be in the manufacturing. Manufacturing defects are usually caught early on, so the drive can be easily replaced if it's still within its warranty.

Improper shutdown can be another reason. Although cutting power doesn't really have any effect on the hard drive's overall life span, it can very easily corrupt files (and data loss), particularly the ones that were in use at the time.

Viruses, trojans and other malware can effectively damage files beyond repair. Keep your computer as safe as possible.

A lot of times there will already be a bad sector created in a part of a hard drive that you haven't used yet. When you do use it, you'll get error messages while trying to access data that got stored there. The problem goes unnoticed more often than not, until that bit of data becomes crucial to your everyday use.

(The causes given above are only a part of how data or the hard drive may get corrupted. The full list is long and technical enough to be left to professionals.)

Minor logical failures (like small bad sectors) are easier to recover data from. All you have to do is take your busted hard drive, use it as a secondary hard drive to a working computer.

To do this, you can either buy a USB universal drive adapter, or get the cables that resemble the ones in use. If all ports are SATA, you can even try plugging the broken hard drive to the cables of the CD drive on the test computer.

If the damage is logical and/or minor, the drives should be visible on the test computer. Immediately get out all your important data and back it up!

Mac users have to plug the broken Mac to a new one using a FireWire cable, then power the new Mac on while holding down the T key. This enables you to use the "target disk" mode that lets the new Mac gain access to the data on the broken Mac.

If the drives don't show up on the test computer, it means the damage is moderate to severe, more likely mechanical (like a damaged read/write head or magnetic disruption). The good news is your data may still be recoverable. The bad news is that it will cost you quite a lot. Not only that, the recovered data won't be just like you had it.

Light to moderate damage can be recovered from, using data recovery software. The cost is variable, depending on the utility and success rate. Basically what these software do is assess whether the data can be accessed electronically.

If yes, then the software will reproduce the data bits on the damaged hard drive and dump it on the new hard drive (which you need to assign. It has to be similar or larger than the broken hard drive). The data will be arranged according to file type in one huge jumble. Some software can retain file names, some will give the files new names.

If this doesn't work either, you'll have to call the experts. Find out the closest specialists in data recovery and give them a call. Their charges will depend on the scale of damage.

No matter what the extent of hard drive corruption, there are only two lessons to be learned here. One, hard drives are destined to fail someday. Secondly, always back your data up. It is imperative that you use data back-up software and get all your valuable photos, videos, documents and other files to safety, before the hard drive dies out.