File Repair Software

File repair software is a utility that finds damaged or corrupted files and fixes them so they can be opened and used again.

A file can be corrupted without being deleted. The storage space is still used and the file still appears in its folder, but its contents no longer make sense. Typical causes are:

• the computer crashing or losing power while a file is being saved
• a faulty USB stick or hard drive that writes data incorrectly
• malware that deliberately alters file contents
• a download or transfer that stopped partway through

You would notice a document that opens as a jumble of symbols, a photo that shows only grey blocks, or a message saying the file format is not recognised. The utility reads the damaged structure, works out which parts are still intact and rebuilds the file.

Repairing, not recovering

Repair means the file is still there and its contents are put right. Recovery means the file has gone, for example after being deleted, and another tool has to hunt for the leftover data. File repair tools do not bring back deleted files, so they are used for their fix-it role rather than to save space or speed up the disk.

A worked example

Imagine your school's media club filmed a presentation and saved it to a memory card, which was pulled out before saving had finished. Back in the computer room, the video file is listed with a sensible size but will not play. A file repair utility reads the file, finds the parts that are still intact and rebuilds a playable copy. The repaired version is saved as a new copy, so the club can check that it plays before deleting anything, and the damaged original is still there if the repair fails.