Secure File Shredder
BitKiller is a small and simple file shredder that you can use to securely delete your sensitive files so that they cannot be recovered with common data recovery products.
In addition to simple overwrites (low level security), the program supports DoD3, DoD7 and Gutmann algorithms, which are more time consuming but offer multiple overwrites for high level security requirements.
by Hasan N. Genc
1) How does BitKiller work?
First, the file to be shredded is overwritten using whichever method
the user chose. Next, the file is truncated to zero size. It is then
renamed randomly ten times. Finally, the file is deleted.
2) Why has BitKiller failed to shred a certain file or folder?
Sometimes, Windows' security features restrict BitKiller's permission
to shred, overwrite, or delete certain files and directories. Try
right-clicking on BitKiller.exe and selecting "Run as administrator".
This will usually solve the problem.
3) I'm receiving an error message telling me my computer requires msvcp100.dll/msvcr100.dll/any other .dll file to run BitKiller.
requires the free Microsoft VC++ redistributable package from
4) Should I always use the Gutmann method?
No. The Gutmann method was designed for an encoding that modern hard
disks do not use. Using the Gutmann method is not only usually
unnecessary, it is also very slow compared to the other methods and
is not likely to be substantially more effective.
Programming, GUI design:
Hasan Nazim Genc
Fatcow Web Hosting
Special thanks to Sasso for his advice and for discovering that the zero-fill function was overwriting files with 0x30, rather than 0x00.