If you need to remove sensitive data totally from your harddisk, simply deleting these files is not enough! Using advanced methods, it is even possible to recover data that’s been overwritten, unless it has been overwritten using carefully selected platterns!
Operating systems usually do not totally delete the file, but just mark the file as being ‘deleted’ so it can not be accessed when you view the contents of a directory. This means that you can not see the file anymore with normal tools, but specialized recovery tools can still access your data.
To prevent this from happening, you need to totally erase your files, using one of the specialized data removal tools you can find in this section. These removal tools totally erase your data by replacing the contents of your files with effective data-patterns before deleting them the normal way.
After Work
Free Windows utility which can be used to wipe sensitive data from your computer, such as: temporary internet files, IE history, visited sites, opened documents, started programs, temporary registry values.
CleanDisk
Non-free. Total deletion of files, clean the Windows swap file, clean temporary files. Contains disk viewer to view the real contents of your disk including ‘deleted’ entries. Suitable for Win95, Win98, WinME, WinNT, Win2000, WinXP.
Eraser
Freeware for Windows. Eraser can remove sensitive data from your hard drive by overwriting it with carefully selected patterns. You can drag and drop files and folders to the on-demand eraser, use the convenient Explorer shell extension or use the integrated scheduler to program overwriting of unused disk space or, for example, browser cache files to happen regularly, at night, during your lunch break, at weekends or whenever you like.
HandyBits file shredder
Freeware for personal, non-profit use. Can overwrite files with random data up to 15 times. Multi-language support, integration with Windows Explorer, with icon on desktop to use as recycle bin, etc.
How to destroy a CD or DVD
Don’t just throw away your CD’s and DVD’s when they contain personal or sensitive data. First you need to make sure that the data is unretrievable.
KillDisk
Harddisk, floppy and partition eraser. Free and non-free editions are available.
No File Recovery
Free disk wipe utility for Windows.
SuperShredder
Freeware. SuperShredder gives you the ability to delete files using not only common methods such as Gutmann and NISPOM (DoD), but can be completely customized to give you all the security and/or performance you may need. It can receive files via drag-and-drop onto the application or the icon, selecting files from inside the program, command line, and can even add a shortcut to your ‘Send To’ menu inside the Windows Explorer so it’s simple to delete files in a secure and convenient fashion.