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Recovering Deleted Files

When you use your computer, you usually move files, delete, create and edit documents constantly. Usually, you can perhaps clean up your computer, deleting old and unused files, and it can happen that you accidentally delete files.

In Windows, there is the Recycle Bin feature, which allows you to recover deleted files, however, there are people who constantly empty the Recycle Bin, or delete files directly using the SHIFT + DEL combination, which they ignore the recycle bin and delete directly.


When you delete files and delete them from the Recycle Bin, many say that the file is lost, but in reality, physically it is not.

Every time the file is deleted from the file system, a question mark is created in the file name, usually in the last character of the extension for files formatted in the FAT file system, and in the case of NTFS, the first character of the name , preserving the extension intact.

At the time of Windows 3.11 NT, there was a recovery program that did practically the same function as the Recycle Bin in Windows 95, 98, XP, Windows 7, etc., with one big difference: It saved disk space.

Undelete, was a famous data recovery program, and the only thing it asked for was to type just the last character of the missing extension, which the file system replaced with a question mark.

For those who do not understand much about the file system on a computer, the interrogation character has the meaning of a wildcard, that is, any character inserted in place is valid, but not valid to display in the context of files, that is, a file it cannot have a question mark in its name, or if the user was allowed to type, he would be deleting the file.

The great reality is that no system physically deletes the file, but only changes a single character of the name to make it unrecognizable by the system, making it deleted, but it is not.

The big problem behind this is the fact that, the file does not exist, the area where the file information is recorded, is marked to be overwritten by any other file or program, that is, the longer it takes to recover the file. deleted file (partially permanently), it will be impossible to recover it.

It's like a K7 tape. I know it's an old thing but the example will do. Imagining that there is a recorded song, and suddenly you throw this tape in the middle of the blank tapes to be reused. The reality is that you have marked that the tape has nothing important, but has audio recorded on it, but is ready for reuse. Imagine that before playing in the blank tape box, recording a sound of silence on both sides, simulating that you are erasing the tape, wouldn't it take longer? This also occurs on the computer. Deleting files would be as time-consuming as saving files, so it is much faster to just write a wildcard in the name for the file to disappear from the file system.

However, the attention is great since the file area is marked as useless, so to speak, and can be overwritten by any program active on the computer.

So, for this, there is the utmost caution in using a computer with several files deleted accidentally.

File recovery technicians do not start the disk on a Windows computer, as this system uses a random recording method that is not controlled by the administrator user, but by the operating system that is closed to the user. Usually technicians use systems like Linux or Mac OS X to recover these files. Although Mac OS X is a proprietary and closed platform, studies show that it is as secure as Free BSD and systems like UNIX, which do just what the user wants, without having "secrets" manipulating data in their operating core.

However, these recovery programs only assign the letter to the wildcard, usually putting a character like an "_" (underscore) in place.

The risk is that not all data can be recoverable, as files can be overwritten by others, at the risk of losing data.

In addition, there are good programs for the Windows platform, which currently do the good job and for free, such as Recuva, which I myself had to use weeks ago to recover data from an accidentally formatted memory card. I managed to get 700 photos, recover almost 600, that is, the person formatted and did not use the camera to photograph any more photos; and besides that, although some of them are lost, or corrupted (photos in half, due to overwriting), I managed to recover photos that had been deleted on the card for years.

For more information about Recuva, visit the website: http://www.piriform.com/recuva
The photos were recovered with the free version of the software and it is very useful for cases that need to recover files accidentally deleted in Microsoft Windows.

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