When you delete a file in Windows and empty the Recycle Bin, the physical space that the file occupied becomes available for other files. Until the space is overwritten, however, it still contains the old data. If you are selling or donating an old computer system, you want to be sure that the new owner wonÆt be able to recover any sensitive data that you thought was gone for good.

You may already have a program that can overwrite data so it can't be recovered. For instance, Norton Utilities comes with a program called WipeInfo, which will securely delete a file, folder or the free space on your drive. Or with Mijenix PowerDesk Utilities 98, you can render a file irretrievable by highlighting it and selecting File-Destroy.

If you don't have either program, download Jetico's BCWipe from www.jetico.com/download.htm or get it off our cover CD (it's free for non-commercial users). BCWipe integrates with Windows Explorer (see FIGURE 2). To wipe a file off of your hard drive, simply right-click it in Explorer and select Delete with wiping. To wipe deleted files, right-click the drive and select Wipe free space.

Windows doesn't completely erase files when it deletes them, but BCWipe does.

A quick-and-dirty way to overwrite deleted files is to run Windows' Defrag, which moves files around on your hard disk, thereby overwriting many sectors occupied by "ghost files". The success of this method, however, is not guaranteed, as it does not overwrite every sector.

-- Lincoln Spector