Data Recovery Tools and Techniques

Here is a very common scenario when working with data: you want to access what you stored and you get an error stating that the data cannot be accessed or the media just doesn’t respond.

Although this may be a terminal situation, many times when data in a storage media cannot be accessed, you can resort to data recovery tools or techniques and hopefully most or all of the data can be recovered. Data may often become inaccessible due to damaged, failed, or corrupted storage media. These media may include hard drives, tapes, CDs, DVDs, RAID disks, or any other type.

Damage to storage media may occur either due to physical damage to the storage device, or logical damage to the file system, or in the worst case, both.

So, how do we recover the data?

In the case that there is physical damage to the storage media, it is mostly due to scratches on the surface of the media (such as CDs or DVDs) or mechanical failure (in the case of hard drives). When physical damage occurs, most probably some data will be lost and become irretrievable. What we need to do is try to salvage the data that is not on the part of the media that has the physical damage. In order to do so, we must keep in mind that physical damage may also lead to logical damage, so we should deal with the logical damage first before any data can be recovered.

In many cases of physical damage, recovery will only be possible through data recovery companies or experts that have the appropriate tools and knowledge to do so. These companies normally apply hardware repairs and/or disk imaging to recover the lost data, and most of the times, much of the data is recoverable. Keep in mind that there are various levels of expertise and tools for this process, and the amount of data that is recovered may vary according to the company or professional (and cost) involved. This is mainly due to the fact that there are easy ways of proceeding, like opening the hard disk and replacing a broken piece, or using highly specialized tools to recover the data. Just how much you wish to spend on data recovery will of course depend on the importance of the data that has been lost.

As an important tip to avoid these situations, make sure to back up your data frequently. If all or most of your data is backed up, whenever your primary data storage media gets damaged, you can resort to your back ups and just repair the physical damage on, for example, your hard drive without the need of the added expense of data recovery by an expert.

On the other hand, is data is lost due to logical damage, there are many tools available (many for free) to recover your data. The most common and basic utilities for data recovery are even included with your operating system, for example:

-         Linux – fsck

-         Mac OS X – Disk Utility

-         Microsoft Windows – chkdsk

However, due to the fact that data sometimes cannot be recovered on a running system, you may need to use a boot disk, CD, or other bootable media with a minimum set of operating system files to start your computer, and then apply any disk recovery software.

Additionally, you can find many types of specialized software that you can use which will do the job and recover all or most of your data after logical damage. Just do a search in any search engine using “data recovery tools” or “data recovery software” and you’ll find an extensive list that you can browse to find what is most appropriate for your needs.

So, start off with the tools provided with your operating system first, and if you can’t recover the information you need, move on to free data recovery tools which may help you. If you still cannot recover the data, you will then have to consider the cost of specialized paid software to do the job.

Again, in this case remember: back up your important data frequently and avoid nasty surprises.