Data Recovery is the process or retrieving lost, deleted, unusable or inaccessible data that may be lost due to various reasons. Not only does data recovery restore lost files but it also recovers files which may have been corrupted. Data recovery is necessary when the source drive fails and there is no good back up.
There are two reasons why a source drive may fail;
1. Damage to the media and the pre-existing data needs to be retrieved. This normally requires the media to be repaired. Media is the Service Area damage, platter damage, head damage or electronic damage
2. Files were purposely or accidentally deleted and there is no damage to the media.
Usually, there are four phases when it comes to successful data recovery, though that can vary depending on the type of data corruption and recovery required.
Phase 1: Repair the hard disk drive
Repair the hard disk drive so that it is running, or at least in a suitable state, that allows the data to be read from it. For instance, if heads are bad they need to be changed; if the PCB is damaged then it needs to be fixed or replaced; if the spindle motor is bad, the platters and heads should be moved to a new donor drive.
Phase 2: Copy the drive to a new drive or a disk image file.
When a hard drive fails for any reason getting the data of it is of utmost importance and should be number one priority. The longer a person makes use of a faulty hard drive the more likely further data loss could occur. Creating a copy of the hard drive ensures that the is a secondary copy of the data from which one can perform testing without further harming the data which is to be recovered.
Phase 3: Logical Recovery of files
Once the drive has been copied it is then possible for one to attempt to recover the lost data. If the drive has failed logically, there are a number of reasons for that. Using the copy, you have made, it may be possible to repair the partition table, MBR and MFT in order to read the file system’s data structure and retrieve stored data.
Phase 4: Repair the retrieved files
Damage to files can be caused when the file is written to a sector on the drive that was damaged. In a failing drive this is most common and files need to be reconstructed in order to open the file and read the file again. Corrupted documents can be recovered by consulting a company that specialises in data recovery service, one such company is Intratec Data Recovery Services based in the north of Johannesburg.