Unfortunately, most home users, and many business users, do not back up their systems. Moreover, many small businesses have older back-up procedures that are often ineffective for recovering files.
Of course, you can run down to your neighborhood electronics store and purchase a replacement drive for your computer, but what about your data on the failed hard drive? How important was it? Did you save it or back it up?
What to do:
If you need to recover data on the hard drive, the first thing to do is avoid trying to reboot or doing anything that involves the drive. Doing so can actually do more damage to your data.
The only irreversible data loss is caused by overwriting bits, physical damage to the drive platters or destruction of the magnetization of the platters, which seldom happens in the real world. In the majority of cases, the malfunction is caused by a damaged circuit board, failure of a mechanical component and crash of internal software system track or firmware.
In the case of actual hard drive failure, only a data recovery professional can get your data back. And the fact that you cannot access your data through your operating system does not necessarily mean that your data is lost.
As a "rule of thumb," if you hear a clicking sound emitting from your hard drive, or if the computer's S.M.A.R.T. function indicates an error during the boot process, something is wrong. You should immediately stop using the hard drive in order to avoid causing further damage and, potentially, rendering the information on the hard drive unrecoverable.
After receiving your failed hard drive, a data recovery specialist's first step will be to try and save an image of the damaged drive onto another drive. This image drive, not the actual damaged drive, is where the data recovery specialist will try to recover the lost data.
The next step in the imaging process is to determine if the hard-drive failure was an actual malfunction, a system corruption or a system track issue.
System corruption and system track issues are normally fixed by using a specialist's data recovery software. System corruption or system track recoveries do not require processing in a clean room environment.
Unfortunately, damage to a drive's circuit board or failure of the head drives is not uncommon. In each of these failures, a data recovery specialist should work on the system only in a clean room environment. There, the specialist can substitute parts such as drive electronics, internal components, read/write arms, writing/reading heads, spindle motors or spindle bearings from a donor drive in order to gain access to the data on the failed hard drive. In most cases, the data recovery specialist is able to retrieve and return the lost data.
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