User:DavidB4/workspace

Logical damage

Logical damage is probably the most common problem which requires recovery. There can be several causes for this kind of problem.

Accidental deletion

It is not uncommon for someone to have a problem where they accidentally delete one or more files. Many operating systems offer a "trash can" or "recycle bin" which holds deleted files in case someone changes their mind or deleted something by accident. However, even if a file is fully deleted, it is not immediately lost. Rather, the pointer to it in the file system is removed, and the space is marked as available. With nothing but a shareware program, much data lost in this manner can be recovered by the user. Some programs such as Recuva look for complete files marked for overwrite only, but others like DiskDigger scan the disk surface to find recognizable patterns. This results in the discovery of many partial and corrupted files, but also is more likely to locate the desired file(s).
If accidental deletion occurs, a user should try to avoid saving any new information to the drive until the lost file can be recovered. Ideally, the recovery program would be run from another partition or drive, and if it was lost on the system drive, the operating system would not be running.

Overwritten data

Wanted information sometimes gets overwritten after it is marked as deleted. Since the operating system sees it as free space, data will simply be written to that specific sector or group of sectors almost completely destroying the old information. This prevents simple disk surface searching from finding what is wanted, but some trace of it can still exist. This trace usually exists in the form of stronger or weaker than average magnetism on a hard disk drive. Such minute differences cannot be read by a conventional computer system, but specialized software can be used to detect and interpret them.

Malfunction

Especially when a storage device is getting worn out, it may eventually start having problems which prevent some data from being read or written. Although difficult, some information can often be recovered after this type of damage has occurred.