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The Destroy Files... action securely deletes selected files by overwriting their file space, preventing file recovery. The dialog allows
Today's computer stores much more than just games and documents; many users access secure websites using password protection to
The computer of such a user likely contains records of such transactions which, in the wrong hands, could lead to identity theft, or worse! Although encryption is often used as a security measure, it has already been shown that RSA public key encryption - once considered unbeatable (even using sophisticated computers) in less than thousands of years - may be hacked under certain conditions in as little as several days. In short, we must always think about
Most of us know that deleted files can be recovered fairly easily by tools such as Recuva, a freeware product. But today computer forensic tools can be used to read residual magnetism on hard drives, possibly re-constructing portions of data that could be used unlawfully. Secure deletion of files - in a way which renders them unrecoverable - is one simple way we can safeguard some of our personal data.
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Info: USB flash drives, although not magnetic, may still be recovered in a manner similar to hard drives. Secure deletion can be useful for flash drives as well. |
The Destroy Files (secure deletion) routine performs the following tasks on each file:
Destroy Files writes data either once or three times, one byte at a time, and is, therefore, somewhat disk intensive. What this means is that the routine is not as fast as normal file writing. Calculation of an estimated write time would be difficult, since it would be dependent on a number of uncertain aspects, namely
Attempting to use Destroy Files on a large file may create a very long wait time, so the following estimates are included here for reference and comparison:
The times for the USB drive are shorter, I believe, owing to the larger drive capacity (shorter seek time). To put these times into perspective, for the listed hardware, one could estimate the secure deletion times as
This means that deleting a DVD image file (± 4 Gb), for example, using 3-pass secure deletion, could take as long as 11.5 hours! Sleep on it!
On the hardware listed above, the Windows Task Manager reports that Explorer++ is using between 95% and 99% of the CPU time during a Destroy Files operation, despite the fact that the process is operating at Normal priority. The effect of this is that
If Destroy Files is launched in error on a large file (see times above), it can be prematurely terminated using the Task Manager by
The effect of this is to forcefully close Explorer++ and, of course, the Destroy Files dialog (a child window), freeing up your system resources. However, take note that
Although the Destroy Files action is deemed to be secure, Explorer++ is released under the GNU General Public License and no warranty as to suitability is offered. Section 15 of the GNU license states that the program is provided "as-is" without warranty of any kind.
In other words, if you use the Destroy Files routine, and you still get busted for importing ivory when the Police seize your computer and find your files, you're on your own!