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How To: Securely Erasing USB Connected Hard Disks

The conventional methods of destroying data on a disk all relate to connecting the drive physically to a computer and using some sort of bootable media with an application on it to destroy data on the connected hard disk in a secure manner. This is the conventional way. I wanted a method that would be faster and more versatile than this, so I attempted to look for a free way to destroy data securely on an externally connected USB disk in Windows.

I wanted to use the external USB connector I purchased for less than $30.00 to take drives that I wished to dispose of (or re-use) and in the fastest possible method, connect, securely erase the disk, remove it, connect another, and securely erase – and so on. This would be ideally done in Windows since the detection of USB devices is hot swappable – I would never have to reboot the computer. Another thing i should mention – there are a number of utilities out there to delete free space and file-used space like Eraser and Sdelete – these are great free utilities but they don’t fit the bill because they work on the file-level. What I’m after is the ability to work on the entire drive and do a full sweep, minimizing the need to handle files and directories and possibly the permissions on them.

In Windows

It seems my biggest hurdle is how Windows handles the drive when it detects newly attached storage. Since, I’m using a beta of Windows 7, there are more unknowns than not. Also, I haven’t managed to find an application that would also run in this beta of Windows 7 to provide me with the ability to erase the drives in question.

One promising application was Active Kill Disk for Windows , this is a free application that seemed well-suited for the task. It did not, however, run in the beta of Windows 7 that was loaded on this computer. I expect this may work on Windows XP if I had it loaded, but a re-install was not in the cards. It crashed immediately when I loaded the application. I then looked to a small shareware utility named BCwipe 3.0, this utility did not work on the drive level, only on the file/directory level.

Reverting to bootable media

Reverting to this type of media gave me full access to the drives on the system – but then created another issue. What of these programs would support the ability to wipe USB connected drives?

I tested Darik’s Boot and Nuke 1.0.7 disk and this utility did not detect my USB disk. I then tested the Active Kill Disk bootable CD and this utility was unable to see the externally connected USB disk. I was becoming somewhat discouraged at the prospects. Utility, I connected with a friend who used the commercially available Acronis Drive Cleanser. This utility boots off a CD and recognizes all USB drives (as well as local drives) allowing for a secure disk wipe.

So, if your looking to securely erase USB attached drives inside of Windows, and do it for free, there aren’t many options at all. In my scenario, I would use the open source utility named Eraser and do a file-by file erase or, to do a full drive erase, use Acronis Drive Cleanser.