Around 44% of all data loss is caused by hardware failure. It's important to make sure that you immediately shut your system down if you suspect that hard drive has crashed. Don't even try to go through the shutdown procedure, just pull the plug from the wall. Do not try to run off the shelf data recovery software or drive utilities. Many times these applications will assume the drive is functioning properly and will increase the risk of permanent data loss.

When we discuss data recovery, we will primarily focus on issues surrounding hard drive failures; since these types of failures are most common. There are really two primary forms of failure in a hard drive, logical and physical. Logical failures are usually a result of file-system corruption. This can occur due to a virus, accidental deletion of key files or registry components, and in some cases even electro-static discharge. In most cases where a logical failure has occurred, the drive is still recognized by the system BIOS, but it will not boot. In most cases, your data should still be intact on the drive, even though it may appear to be inaccessible.