Every hard disk eventually fails and Murphy’s law dictates that the odds of a hard disk failing increase dramatically if the drives contents have not been backed up. So what can you do if a disk filled with irreplaceable data fails and you don’t have a backup?

The first thing that you will need to do is to determine the nature of the failure. There are two main types of disk failures and the recovery technique that you will need to use varies depending on the type of failure that has occurred.

The first type of failure is a physical failure. This type of failure occurs when the drive’s physical components break or wear out. When a physical failure occurs, you may hear the drive making a loud clicking sound. Conversely, the drive might be completely silent if its motor has gone out.

If you suspect that a physical disk failure has occurred then there is both good news and bad news. The good news is that your data probably still exists. The bad news is that getting the data back may prove to be expensive because your options for do it yourself recovery are very limited.  Your best chances for recovery are to use a professional hard drive recovery service, The Data Rescue Center offer pricing that is 30 to 40 percent cheaper.

If you believe that a physical disk failure has occurred then you might try removing the disk from the computer and then temporarily connecting it to another computer or to a USB adapter. There are situations in which a controller failure, a bad SATA cable, or even a faulty power supply can mimic some of the symptoms of a physical disk failure. Connecting the disk to another computer or using a USB adapter bypasses these hardware components and will allow you to either access the data or confirm that the disk has failed. If you do determine that the disk is bad then your only option is to send it to a data recovery center, which typically costs at least a couple thousand dollars.

The other type of disk failure that can occur is a logical failure. When a logical failure occurs there is no hardware level damage to the disk. The motors, heads, platters, etc. are all still functional. Instead, some sort of data integrity error has corrupted the contents of the disk. This might happen as the result of a virus, an accidental formatting, a power loss, or any number of other factors. The good news is that there is a very real chance that you will be able to recover most, if not all of your data after such a failure occurs. The key to doing so is having the right tools.

There are two main things that you are going to need in order to recover your data after a logical disk failure. First, you are going to need a data recovery utility. Prosoft Engineering makes an excellent tool called Data Rescue that you can use. The other thing that you are going to need is a second hard disk.

The way that the recovery process works varies depending on what tool you use. Some tools do a better job than others, and some of the tools on the market can actually jeopardize your data during the recovery process. Prosoft Engineering’s Data Rescue takes a safe approach to the data recovery process, which is why I like it.

When you are trying to recover data from a failed disk there are two things that you must be sure to do. First, you need to minimize further wear and tear on the drive just in case the heads are wearing out. Second, you must avoid making in place repairs because the repairs can overwrite good data.

The Data Rescue tool resides on a bootable USB drive. Booting from a USB flash drive helps to minimize disk wear and it avoids the problems associated with booting from a potentially damaged boot sector or operating system.

Once the software has been loaded, it scans your hard disk to determine what data is recoverable. Recovered data is written to a secondary hard disk. This avoids further disk wear and places recovered data onto a known good drive. More importantly, this process eliminates the possibility that good data will be overwritten during the recovery process.

Unfortunately, it’s impossible to guarantee that data can be recovered following a hard disk failure. Even so, tools such as Data Rescue that adhere to a best practices approach to data recovery have surprisingly good odds of being able to get your data back, and for a reasonable price.