In the previous article, Permanent and Reversible Data Loss, we discussed the various situations that can lead to the loss of data. From practical point of view, it is essential to be able to tell one from another. It is very difficult to damage a modern storage device beyond repair (or, rather, beyond the point at which a data recovery operation is still possible). This article tries to give hints as to how particular situations can be successful handled in the most economical way.
Empty Volume
The disk can appear empty in many situations. Accidental formatting, file system corruption or mass deletion can render the disk empty. Fortunately, this situation is often recoverable. Commercially available tools such as HDD Recovery Pro can deal with formatted partitions, corrupted file systems and deleted files rather easily and economically. If you’re looking to recover a single volume and know it was formatted with either FAT or NTFS, you can realize further savings by opting for a file-system specific tool such as NTFS Data Recovery or FAT Recovery. Note that those very tools can be used in other situations described below.
Inaccessible Disk
If the disk still appears as a drive letter, but you can’t access it or see an error message when attempting to open it, most probably some system structures of the disk are damaged. Sometimes this is also accompanied by heavy wear (excessive number of reallocated and bad sectors), which makes the recovery attempt somewhat less successful, as some files may be only partially recoverable. Try recovering data from an inaccessible disk with one of the tools mentioned above. HDD Recovery Pro may be particularly effective in this case.
If the attempt is unsuccessful, try bringing or mailing the disk to a data recovery company with a clean lab. More often than not, the data can be recovered, and your total bill could to around $300-700.
Disk Does Not Appear as Drive Letter
If you don’t see a disk appearing as a drive letter, this may indicate logical corruption of the partition table and/or the MBR. Alternatively, this might be a sign of a deeper issue. If the disk is recognized by the PC and appears in the list of connected devices in either Windows list of System Devices Trying or at least in the computer’s BIOS, running a data recovery tool such as HDD Recovery Pro is still the first thing you should do. If that does not help (e.g. the data recovery tool does not see the physical device), you can try attaching the disk to a different PC and see whether it’s picked up by the new system. If it is, the issue might be with the original computer’s motherboard or SATA controller. If the disk is not recognized by the system BIOS, the only thing you can do about it is sending it to a clean lab. Depending on what exactly failed in the disk, your total recovery bill may range from about $150 (failed disk controller, excessive wear damaging internal system areas etc.) to about $700 (failed heads or other damage involving the extraction of the actual magnetic discs). It’s up to you do decide if your data is worth it.
