The recovery data (or data recovery), in computer science, is to recover data from storage media when they are damaged, corrupted or inaccessible. 

In the field of criminal investigation, the recovery is to recover material previously transited and / or deleted, on computers of people under investigation. 

The storage media that may be subject to recovery are virtually all storage media, although the most common are in order: hard disk, USB removable media (USB key), memory cards, floppy, CD, DVD, tape, magneto-optical media. 

The damage of the media can be either physical or logical type (in software), and can cause sudden stops or unavailability of the system and / or data.

More than 30% of cases it is estimated that recovery of data is impossible because of human and not to damage hardware. 

Kroll Ontrack leader in providing solutions for backup and data recovery services has drawn up a list of those that are the most common errors that users make when there is a problem of loss of data on the hard disk of their computers, as well as give some tips on what to do and what not to do when faced with a similar case. 

- Conduct in hazardous situations damaged hard disk are certainly to be avoided. The do-it-yourself, without an adequate knowledge of the hardware and the necessary technical skills, can lead to total compromise of the device, making impossible any future attempt to retrieve data 

- Clean the disc. In most cases, the user proceeds to format the disc after restoring data from backups made previously. Once you clean the disc proceeds like a script for a new installation of software such as operating system and various applications. Although the transaction does not appear to be the most complex, but often one realizes too late that their backup is not updated or worse does not work. In this case there are solutions that allow you to recover data. The Board, however, is always to check the operation of the backup and its status update before proceeding to the formatting. 

- Substitution of components: It often happens that in case of malfunction of the hard disk you try, improvising technical, to replace the failed drive by purchasing a similar, without considering that the components of a hd containing information of its membership drive the technical specifications of its new component, and especially that opening up the disc in unfit environments can cause irreversible loss of data. 

- Block of the disc, or if you find that the drive and the heads are firm, for example because there is no noise due to the normal rotation of the flat disk, the most common mistake is to remove the disc and or try to shake him of taps, hoping to break the deadlock. Nothing more wrong! because it threatens to severely damage the disk at the physical level. In these cases is often that the head that graze the surface magnetic rovinino the surface of the plate that contains the data making it impossible to scratch and all future reading. 

- Infiltrations liquids such as the overthrow of a glass. The same remedies are used, such as groped to dry the disc with a hair dryer, with the danger of only worsen the situation. The appropriate behavior in these cases is to keep the drive moist, thus preventing the impurities will be established on the plates inside the drive and contact the assistance of a professional provider of data recovery.

- Using improperly system utilities for recovering data. It is a strong temptation for the user who faces the risk of losing valuable corporate data, to use them. Classic examples are CHKDSK, Mac Disk Utility or fsck. The problem is that if the drive is physically damaged the use of these programs has resulted in further damage to the hard disk, making it harder to recover data. 

Conclusions: In most cases, do not improvise technical do-it-yourself but contact an expert who knows how to resolve the situation and prevent loss of information. In over 80% of cases, you can retrieve the full content of the medium, even in cases apparently insoluble, but you do know! 

Often a program for recovering data can help you recover lost files or corrupted hard disk. We report the data recovery software for more effective. 

Trying to repair the error yourself, if you do not have the necessary expertise and equipment, can result in exacerbating the damage. If you suspect that there may be a loss of data: 

Do not lose heart 

Turn off the power supply 

Do not reboot the machine 

Do not reinstall any software 

Do not open the hard drive or try to repair it yourself 

Assess the situation 

The first thing to do is ALWAYS turn off your computer. Any attempt to solve the problem could undermine ulterioriormente the situation and make the recovery data 

Do not reinstall the operating system as this could lead to a rewriting of data onto the disk and worsen the situation. 

In the case of head-disk drive crash audible sounds are often very high, connected to a rubbing noise. In this case absolutely not to restart the computer, as this could irreparably destroy the data it contains. 

Do not ever groped to solve the problem. Do not hand the hardware and not shake the data by removing the protections of the hard disk. 

If the problem was caused by flooding of the premises housing the PC, do not ever groped to dry the damaged data from an inappropriate treatment, such as the typical hair dryer. 

Sometimes, you can retrieve the data compromised in fully automatic mode, using special software. It 'still not recommended to use this software if the symptoms suggest a hardware failure or if the computer produces abnormal noises. 

The loss of data can have several causes: viruses, accidental formatting, mechanical failures, deleted files, blocks of the system, errors in the partitions, electrical, accidental knocks. 

For this it should be remembered that the problem is not asking the question "if" the data will be lost, but what to do "when" this will happen. 

These are some typical warning signs that might give the system: 

Error message, the device is not recognized 

Data no longer available 

Abnormal noise or hiss coming from 'hard disk 

Hard drive not moving 

None of the hard disk operation 

Too often we tend to overestimate the reliability of a hard disk. The data contained within a personal computer is often a great value.

Activities of firms depends on the data in their systems, databases or files from its operational and working. The only backup of these files sometimes is not enough, because the damage and the potential disaster is often very unpredictable and come in less expected moments. It's therefore useful to have some knowledge on the "recovery" being the action to recover files from a damaged magnetic media. 

The term "data recovery software" is, in general, indicate the category they belong to several programs that allow us to remedy problems that may threaten the integrity and accessibility of data in our computer or in our removable media. I like, very, defining them as "the last bastion in the defensive struggle between the computer user and the machine" in the sense that their use is the last chance we have at our disposal to resolve the most "dramatic" situations that have to create after sad loss. 

According to the rushed nature of the incident, then, the type of damage caused, you can make the following distinction: 

1. software for data recovery after loss caused by accidental deletion 2nd software for data recovery after formatting loss caused by unintentional

3rd software for data recovery after a loss due to virus problem 

4th software for data recovery after loss caused by dysfunction of 

5th software for data recovery after loss caused by physical damage to the disc 

Virus, disk crash, poor safety routines, lack of maintenance errors during upgrade or installation of software or simply the consequences of an accident may have caused the loss of data. Even in extreme situations: the unit of storage may even have been submerged in water or involved in a fire. 

The hard drive is placed on the test bench and tested to see the problems of the drive. 

There are several rounds of tests, from which we try to deduce what processes will be needed for recovery. Based on these will be completed prior to the attempt to recover and to restore itself. 

Begins processing, which can last from a few days to two weeks, depending on the availability of parts and complexity of the intervention. 

More delicate and at the same time more difficult to use, so often used by professionals, are the software for data recovery in the third and fourth category. 

Generally the damage caused by destructive viruses or software malfunctions of the file creator, are quite serious in some cases, part of the data may be corrupted as to affect the entire recovery, allowing only after a thorough analysis, a partial recovery.