• United States



by Brandon Gregg

How to Protect Your Privacy from Computer Forensics

Jan 06, 20104 mins
Investigation and ForensicsPrivacy

Concerned about identity theft? Selling or recycling an old computer? Corporate investigations manager Brandon Gregg explains three tools for making sure your data is really deleted.

Anti-forensic tools and tricks aren’t just for hackers and bad guys trying to cover their tracks. In a world full of online privacy concerns and rising identify theft, there are easy-to-use programs that completely erase data from even the most prying eyes.

Although many people know how to occasionally clear out their internet history or uninstall a program, these ‘deleted’ files are still easily accessible with ‘data carving’ tools that bring even partial information back to life. Using the following three free programs you can securely remove data from your computer and prevent it from returning from the grave to haunt you.

Also see Gregg’s Tools to Identify Anonymous Users Online

With over 350 million downloads, CCleaner is your first stop for quickly cleaning out many of those hard-to-reach files. From temporary files, Internet history, cookies, download history, auto complete forms and index.dat files in five major browsers to cleaning out the recycle bin, recent documents, windows log files, old registry entries and many more third party files, this program is a great one stop shop.

After downloading the freeware program, go straight to the settings tab and turn on “Run CCleaner when the computer starts”. Next select Secure file deletion and choose the Simple Overwrite option which writes random data over your deleted files one time. This option is sufficient for erasing your data from professional forensic recovery software such as Encase and FTK, but if your paranoia needs to be squelched you can increase the number of times CCleaner writes on top of your deleted data to 3 passes (DOD 52202.22-M), 7 passes (NSA) or 35 passes (Gutmann). Once this is set up, run the program to clean out your system. You may even notice an increase in computer speed and extra drive space. Going forward your system will clean itself of the aforementioned files during Windows startup.

The second piece of software is for strictly wiping your “empty” drive space. Although CCleaner has this option (and you are already using part of it on the selected files above), you have to remember to manually run the program after every document, photo or file you delete. With the open source program Eraser, you can have instant or scheduled erase of individual files, folders and drives. Simply install Eraser on your computer and select Preferences to turn the scheduler on at Windows startup. Next, go to the Scheduler tab and select New Task to pick your drive locations, level of passes on the deleted data and erasing schedule.

Once complete, Eraser will run over your empty drive space and clear it out as often as you would like. Better yet, file deletion can be set for instant with any Windows files by simply right clicking the file(s) or folder for additional properties. On your menu you can now select Erase to permanently delete your individual file for good.

The last program’s name sums up what the program does: Darik’s Boot and Nuke.

NOTE: Please do not use Boot and Nuke you aren’t knowledgeable about computers; you can turn your computer into a brick. You have been warned!

For a quick and complete erase of all hard drives in your computer, download Boot and Nuke, burn it to a CD and restart your computer. Boot and Nuke will then securely erase any hard drive it detects, including your operating system. This is best to use before selling a computer or throwing away an old hard drive. However, many hackers leave a copy in their CD-Rom bay at all times with their power off button connected to rebooting, such that anyone who attempts to play with the computer will trigger the program.

Don’t forget that the erasing programs above are only good if you use them on a consistent basis and on all your storage media (hard drives, external drives, thumb drives, media cards, etc). Taking these precautions today will secure your privacy for the future.