When you delete a file using Windows, it goes to the recycle bin. When you empty the recycle bin, the file is gone right? Actually no; when you delete a file from the recycle bin (or SHIFT+DEL from Explorer), the file is just dereferenced. As long as the data isn’t overwritten, the file is completely recoverable–and may be for sometime if the space isn’t needed. In this guide, you’ll learn about two tools you can use to permanently delete files from your hard drive: RightDelete (GUI) and SDelete (command line.)
RightDelete is a simple secure file deletion program.
File deletion uses the seven pass method, ie overwriting the content with $00, $ff, $00, $ff, $00, $ff, random(256), before the file is actually deleted and buffers flushed. This will ensure the file is no longer recoverable SO be sure you want to delete the file selected!
To add or remove RightDelete fom the context menu run rightdelete.exe. Adding to the context menu will insert ´Securely delete this file´.
The only way to ensure that deleted files, as well as files that you encrypt with EFS, are safe from recovery is to use a secure delete application. Secure delete applications overwrite a deleted file’s on-disk data using techiques that are shown to make disk data unrecoverable, even using recovery technology that can read patterns in magnetic media that reveal weakly deleted files. SDelete (Secure Delete) is such an application. You can use SDelete both to securely delete existing files, as well as to securely erase any file data that exists in the unallocated portions of a disk (including files that you have already deleted or encrypted). SDelete implements the Department of Defense clearing and sanitizing standard DOD 5220.22-M, to give you confidence that once deleted with SDelete, your file data is gone forever. Note that SDelete securely deletes file data, but not file names located in free disk space.
SDelete is a command line utility that takes a number of options. In any given use, it allows you to delete one or more files and/or directories, or to cleanse the free space on a logical disk. SDelete accepts wild card characters as part of the directory or file specifier.
Usage: sdelete [-p passes] [-s] [-q] <file or directory>
sdelete [-p passes] [-z|-c] [drive letter]
|-c||Zero free space (good for virtual disk optimization).|
|-p passes||Specifies number of overwrite passes.|
|-q||Don’t print errors (quiet).|
|-z||Cleanse free space.|