When a sudden computer hard drive malfunction makes data inaccessible, there is a series of emotions that crop up. The emotions can range from anger to fear. In the first few minutes of a crisis, the sequence of emotions can include fear of being blamed for the failure, a realization that the data on the hard drive is no longer accessible and anger at the “computer gods” for being so mean. The idea of frequent backup suddenly seems very important. There is the hope that the backup is current and useable.
The first step is to check the backup. Is it viable and recent? How can the data be restored from backup and how long will it take? In many cases the restoration from recent backup will recover all but the most recent activity. The situation is rarely hopeless but the most recent data on the hard drive will be in limbo. If that data is valuable and cannot be restored from backup it is time to think about data recovery from a hard drive.
Data recovery from a hard drive can be an expensive, time-consuming course of action and is generally beyond the resources of the home computer user. Data recovery companies exist to serve the needs of business and sometimes law enforcement. Emergency service is often available at substantial additional cost.
The actual reason for the need to recover data has a large bearing on the process used and the comprehensiveness of recovered data. Sometimes a software-based problem can be solved with a software-only process. This process uses specially written programs to recover data from a mechanically functioning hard drive. When a hard drive has mechanical problems or physical damage, the recovery process can be quite involved. Sometimes the drive is disassembled and the data media mounted on another set of mechanicals so the data can be read off the disk(s). This process requires a “clean room” and specialized equipment that adds to the cost.
There are commercially available software tools that can recover data from drives that are not physically damaged. It is possible to recover deleted data, data from inaccessible partitions, raid configuration issues and deleted file allocation tables. Even drives with intentional sabotage or virus-caused data corruption can be recovered. Drives damaged by water or with other mechanical problems will require the services of a data recovery company. Software tools cannot recover data from a drive that is not working mechanically.
Most data recovery services offer assessments and provide a price quote before actually doing any work. The turn-around time is normally five to seven days but expedited services can reduce the time significantly. There are situations where data is not recoverable. Disks can be damaged so severely that data recovery is not possible.
Attempting to use data recovery software on a physically damaged drive can result in more damage to the drive. It is better to have a drive assessed by professionals if there is any chance of physical damage. When the damage is limited, the recoverable data is maximized. If the data contains confidential information, it may be worth the time to investigate the security policies of any recovery company before shipping a drive for recovery. Most data recovery companies have secure facilities and stringent policies to keep data confidential. Companies that offer forensic services for law enforcement organizations have to meet strict rules for chain-of-custody and security so these companies are often good choices for confidential data.