CyberScrub Product Review

Surprise! That File You Deleted - It's Not Really Gone!
Most people think that the simple act of deleting a file from their computer makes it impossible for somebody to steal the data that was contained therein. In truth, the term "delete file" is a misnomer in Microsoft Windows. When you right click on a file and select the Delete option, the file really isn't deleted at all, and it can in fact be recovered with commercially available file recovery software. Deleting the file merely makes it invisible on the directory of your hard drive, but the actual file is still there, as illustrated by this analogy:

When you walk into an office building, the directory in the lobby tells you where Dr. Smith's office is. If you delete Dr. Smith from the lobby directory, his office is still there - it's just harder to find. A similar thing happens when you delete a file in Windows.

Eventually, the file you deleted will be overwritten by another file that you save, but this may take days, weeks, or months. And a file may be partially overwritten, allowing somebody to recover part of the file.

The ability to recover a deleted file is good news if you accidentally deleted something important (but shame on you for not having a backup!), but it is bad news if you sell your computer to someone who successfully recovers your deleted files. This is an all too unfortunate but common occurrence. When asset management firm Morgan Grenfell sold an obsolete PC, the new owner recovered 108 files pertaining to Paul McCartney's personal finances, as well as financial data for other institutions.

Many people also think that reformatting your hard drive deletes their data, but reformatting does not delete the data either – it merely wipes the entire index clean. So once again, a person with a specialized data recovery tool can recover data off of your hard drive.

To truly erase your files, as opposed to "deleting" them, you must use disk wiping software, also known as disk scrubbing software. A disk scrubber is the electronic equivalent of a paper shredder, overwriting files as you delete them with a random pattern of zeroes and ones. (All data on your hard drive is stored as zeroes and ones - every character and number is coded as a combination of zeroes and ones.)

All disk scrubbers provide the ability to erase a file beyond recovery. But what about the thousands of files you erased before you installed a disk scrubber on your computer? And what if you accidentally delete a file instead of erasing it beyond recovery? How can you keep these files safe from prying eyes?

The answer is to use a disk scrubber that also has the ability to go through your entire hard drive and erase all of your hard drive's free space and slack space. Let's explain these very important terms.

Understanding Hard Drive File Management
Your computer's hard drive is organized into physical units of space called sectors into logical groupings called clusters. This is because individual sectors are too small a unit of disk space for Microsoft Windows to effectively manage. By design, the cluster is the smallest unit of space on your hard disk that can be managed by Windows.

The cluster size – the number of sectors that comprise a cluster – is a function of three things: (a) what version of Windows you have installed, (b) what file system your version of Windows is using, and (c) the size of your hard drive.

When you delete a file, the clusters that were occupied by that file are now available for use. These clusters are now free space. They still contain data, but Windows is “free” to overwrite the data in these clusters.

A particular cluster can only contain one file, but a file may span many clusters. The last cluster that a file occupies may contain unused space, referred to as slack space.

It would be wrong to equate slack space with empty space – space containing no data. When Windows stores a file in a cluster, the file may not require as much space as the file that previously occupied that cluster. This may leave remnants of older files in the cluster’s slack space.

A Misconception About Disk Scrubbers
Some people are under the mistaken impression that a disk scrubber wipes everything off their hard drive. This is not true. A disk scrubber does not harm your operating system, applications, or data. It merely wipes free space and slack space.

Unfortunately, most disk scrubbing software only allows the user to erase a file as it is being deleted. That is, they do not provide the ability to wipe free space and slack space, thereby erasing any files or file fragments from files you deleted in the past. A few of the better disk scrubbers provide the ability to wipe your hard drive's free space, but we have found only one product that erases both free space and slack space: Cyberscrub.

Cyberscrub has a friendly user interface that integrates into Windows' right-click menus, adding the choice "erase beyond recovery" to the other menu choices.

Cyberscrub's user interface is simple and easy to understand. The initial screen gives you four, clearly explained options:

When you choose to erase previously deleted files, you have the option of selecting your drive(s) and whether to erase slack space as well as free space. You can also tell Cyberscrub to scramble file names on the directory so that not even the file name of an erased file can be recovered.

Cyberscrub provides 10 different methods of wiping previously deleted files off your hard drive, including three methods that go far beyond department of defense standards for data recovery:

The more secure a method you choose, the longer it will take for Cyberscrub to scrub your hard drive of previously deleted files.

Why Multiple Wipe Methods?
Have you ever written something on a pad of paper? If you rip the page off, you can see the impression of what you wrote on the page below. In fact, you may have to rip off several pages to make it impossible for somebody to recover what you wrote.

A similar situation exists on your hard drive. If you only wipe your hard drive once, there is still an impression of the file that previously occupied that space. Performing multiple passes eliminates that impression, the way that ripping off multiple pages of the table eliminates the impression of your writing.

Cyberscrub's Privacy Guard enables you to wipe your Windows swap file clean, as well as your list of recently accessed documents and temporary files created by applications. It also removes all traces of your online activity.

When Do You Need A Disc Scrubber?
At a minimum, you need a disc scrubber when you go to sell your PC. You would certainly want to remove all sensitive data from your PC before you sold it to somebody. You should also use a disk scrubber before you send or take your PC in for repair. Don't assume that all of the employees at the repair center are honest. In fact, you should backup all of your data, delete it from your hard drive, and then erase it for good before you take your computer in for repair. Finally, if you work with critical information every day you might want to use a disc scrubber on a more regular basis to protect yourself from hackers.

Cyberscrub if thorough, easy-to-use, and safe. However, as always, we advise users to backup their hard drive before using such a powerful system utility. At $49.95, it's a steal.