I’ve previously discussed why you shouldn’t just throw out or recycle your computer without wiping the drive first to protect your identity and files in a 404 Tech Support article Before you recycle/garbage that old computer. If you’re deleting files from your computer that need to be kept from prying eyes, you should be using a secure deleting application for the same reason. The open-source application I recommend for that task comes in the form of Eraser 6.
The same analogy used in the previous article holds true for justifying why you should use Eraser 6. A file on a disk can be compared to a house in a neighborhood. In Windows, when you delete a file (even Empty the recycle bin) all you really did is take the address off the house and put up a ‘lot for sale’ sign.
If somebody knows where to look, they’ll be able to find it until a new file comes in and takes over that space. A secure deleting tool comparably bulldozes the house and fills the lot with a bunch of random bricks and mortar with the ‘lot for sale’ sign still up in the yard.
Eraser 6 is a free, open-source application hosted on SourceForge and with its own site at http://eraser.heidi.ie/. The current version of Eraser 6.0.6 supports Windows XP, Vista, and Windows 7. An older version (5.7) is still kept around to support Windows 9X/ME. While Eraser 5.8.8 provides a portable version that you can throw on your USB jump drive to take with you for your erasing needs on the go.
Installing the latest version of Eraser gives you the option of integrating Eraser in the the Explorer context menu. This allows you to right-click a file or folder and choose to Erase the file or Erase it upon restart. You can also drag directories or files into the Eraser window to delete them immediately. Be careful with this latest version though, there’s no prompt for confirming the process. While erasing, the system tray icon (a red nuclear symbol) will pulsate. For single files this will only take a few seconds, but for big files and folders this can take a bit of time. The amount of time taken will also depend upon the method used to write over the files and how many passes it makes. All of this can occur in the background so time doesn’t seem like it should be too much of a problem. A bigger factor should be the resources it consumes as it runs in the background as a service. While Eraser was actively deleting a large directory it used between 55-70MB of memory, while just idling it used only a few MBs.
A cool feature of Eraser is that you can set up tasks. These can be run manually, immediately, or scheduled to run at restart or a recurring time (hourly, daily, or weekly). I like this flexibility because it allows me to adapt Eraser to my needs. Let’s say I make my own “last chance” directory. Any files that get moved into the C:DeleteMe directory will get deleted every Friday at 5:00 or if a log is written every week to a directory and we delete it for privacy reasons after keeping it around for troubleshooting purposes, we could add a directory and filters to only include that file to get deleted regularly. You can also have it Empty and Erase the Recycle Bin contents regularly so you don’t even have to change your regular habits.
You can also configure Eraser so that certain files or folders are placed where the erased files were in case it’s needed for plausible deniability.
You can download Eraser and learn more from its homepage.