The Erase Empty Space tool lets you securely overwrite all the empty space on a hard drive. Any data on the drive won't be affected.

This command isn't exposed in the default toolbars, but you can easily add it yourself:

  • Open the Customize dialog (Settings > Customize Toolbars and Keys).
  • Select the Commands tab
  • In the File Operations category locate the Secure Erase Empty Space command
  • Drag that to your toolbar or menu

The underlying raw command is Delete ERASEEMPTYSPACE.

Using the tool

The tool itself is quite simple to use. A dropdown list lets you choose the drive to erase. You can set the number of passes for secure overwriting - one is usually enough, but you can increase it for greater security. Then click the Erase button to proceed.