What Nasty Stuff Lurks on Your Old Hard Drive ?

A study by two MIT students revealed that the failure to correctly erase old hard drives can create serious security problems.

You can read a news story at

Just putting files in the trash does not erase them! For security you must use a program that writes new, randomly generated, data over the old files.


This free program from the University of Washington is no longer supported. See the next entry for an alternative.
If you still want information on Autoclave, here is the link.

Darik's Boot and Nuke

This is a well reguarded free open source program. It completely erases and over-writes a hard drive. You put it on a floppy disk, or a CD, and run it. This completely wipes the hard drive, including the operating system. (The computer will not start in the normal way after you do this.) Be sure that you scroll down and read the documentation before you do anything else. Note: all disk deletion programs take a long time (many hours) to run
Darik's Boot and Nuke


The program above is for completely erasing your machine, but good practice includes being sure that the individual files which you delete are really gone for good. This free program selectively erases and writes over files. You can use it while you work. It will also clean all of the "empty" space on a disk.
Eraser (www.heidi.ie/eraser/)

Eraser is easier to use than DBAN and should take care of most files. It will not get system files, which might include file names and internet sites visited. The following may seem complicated, but that is just because I am trying to give you every step.
To use it;

For Every Day Use

For Old Files, and Those Deleted From Within Some Programs:

Do you run a business?

You might want to see:
The computer disposal policy of the University of Washington
The policy of the Department of Defense

or try search on "computer disposal policy"