Newest Technologies in Data Recovery

Modern data recovery tools do miracles compared to their counterparts of yesterday. The recovery of deleted files is often possible days and weeks after the files have been deleted, while the recovery of files and data is often possible even if serious damage has occurred to the hard drive. Even if the file system is damaged or completely non-existent, some of the better recovery tools can still hand most of the really important stuff back to you.

Data Recovery History and Technical Background

Years ago, only professional-grade recovery products could yield comparable results when used by experienced data recovery professionals. Today, you can perform the recovery yourself and get your files back completely if you use proper tools. The only question is: what exactly are these ‘proper’ tools?

In order to answer this question and to give you a better idea on why some data recovery tools can work better than others, let’s talk a little about technical background. Technically, when you delete a file or remove it from the Recycle Bin, its content is not wiped off the hard disk. Instead, the file is flagged as ‘deleted’ in the file system, which can be FAT or NTFS in Windows. Note that the original content of the file and its name, size and exact location on the hard drive are still stored on the disk and in the file system. Therefore, it is entirely possible to undo the deletion by unmarking the ‘deleted’ flag. The process is called ‘undelete’.

Such tools existed for a long time, but there is a problem with this method of data recovery. If Windows uses some of the space occupied by the deleted file to store different data, undeleting the file will not only give you an unusable document, but also it will corrupt the file system by creating multiple references to the same space on the hard drive.

Second-generation recovery tools recognize this problem, and refuse to recover files that could cause problems. But what if you really need to get that file back, and it’s just partially overwritten? Certain types of files, such as Word documents, can be recovered and then fixed to conform to the Word standard without a loss if the recovery is done properly.

The third generation of data recovery tools does not mess with ‘deleted’ flags at all. Instead, such tools scan the file system, obtain the exact location of the deleted file on the hard drive, and then copy the original data to a new location, repairing the file format if necessary. Fix My Files does exactly this when recovering deleted files, and goes even further if there is damage to the disk or the file system.

State of the Art

If the hard drive becomes corrupted after a system failure, or if the file system is lost after accidentally reformatting or repartitioning the disk, information from the original file system is unreliable or non-existent. First and second-generation data recovery tools can’t do anything to recover your files. Third-generation tools, however, can still recover the most valuable pieces of information such as office documents, compressed archives, email, digital pictures and multimedia files. The trick here is recognizing the exact location and length of supported types of files by scanning the hard drive directly in low-level mode. Matching information read from the disk against a set of signatures, the data recovery tools can detect the beginning of each file in a supported format. By reading file header the recovery tools calculate the length of the file, which is exactly what is required in order to recover it.

Both Fix My Files and Fix My Disk support this technology when undeleting deleted files, recovering data from damaged disks and corrupted partitions or fixing entire hard drives. Both tools allow previewing recoverable files before performing the recovery in a what-you-see-is-what-you-get fashion. The preview is optimized for safety, and does not write anything onto the disk being recovered. Live preview            works in both full and evaluation versions of the two recovery products, and allows true evaluation of exact recoverability of each file.

Links:

• Buy it on-line.
• Download a fully-functional evaluation copy.