Friday, May 19, 2006

Did You Really Erase That Data?

It's time to upgrade your computer. You've found an excellent deal on a new desktop or laptop and you're long overdue for a faster processor, more memory, a bigger hard drive and an updated operating system. Once the new computer is in place and running the way you want, what is going to happen to your old one? Does it stay in the office for backup? Go to the kids? Join the last five outcasts on the basement shelves? Or will it leave the building?

Most people and companies want to sell, donate or recycle their old computers once they realize they'll never go back to using them again. Setting them out with the trash isn't a good idea because of all the toxic chemicals on the circuit boards. Besides, it's just wasteful. Many schools are begging for recent model CPUs, monitors and accessories. Even older models can still be used for light duty tasks such as email or word processing. A non-working machine can be recycled to recover gold and other valuable materials. Or, the computer can be disassembled for it's working parts just like a junk car. Some unscrupulous people would love to put your unwanted disk drive to good use. That's good use for them, not necessarily for you.

The problem with hard drives is that they are chock full of valuable information, including bank accounts, family history, strategic business information, contact lists and email address books, etc. Your PC hard drive is a virtual diary of everything you've done in the last few years. All a clever business spy or identity thief needs to do is pick your hard drive out of a bin at the surplus store or recycling drum. Or simply buy the whole machine for a few dollars at a second hand store. Someone with ill intent can then plug your drive into their computer and spend many a productive hour exploring your personal data.

But you protest. There is no way anybody can get your data. Before you shut down the machine for the last time, you moved everything to the Recycle Bin and then emptied it. That erased everything, right? Not really. Did you know that you can buy programs that will restore data you accidentally deleted? There's no magic behind this process. When you tell a computer to erase something, it doesn't do it. All it does is take that file out of the index so you can't see it anymore. If your hard drive is absolutely full to limit, some data will be lost when it gets written over by new files. But how many 40, 80, or 160 Gigabyte hard drives are fully used up? You can't count on deleted file space being recycled on a drive that is only fractionally full.

Well, then. Reformatting the drive must get the job done, right? It seems logical because you lose the operating system and all your files when you reformat a drive. But, sadly, reformatting is more like deleting than erasing. The reformat process only erases and rewrites a small part of the disk. The rest of the existing data is ignored and left as-in. Repartitioning won't help either, for the same reasons.

The only sure way to get rid of data on a disk drive is to change it magnetically. That's easy for floppy disks and tape. You can buy a bulk eraser that imposes a high strength magnetic field on the magnetic medium and changes the orientation of the magnetic domains. Whatever was on that disk is gone for good. Disk drives are sealed and not so easy to access. A better way is to use what is called a wiper program to write random data to every sector of the disk. Entropy is your friend when it replaces your vulnerable information with gibberish.

WipeDrive is a low cost commercial software product designed to wipe hard disk drives clean. You pop a floppy disk or CD-ROM in your computer with the WipeDrive algorithm and it scrambles everything on your hard drive. It works by writing random characters with multiple overwrites and verifying that the overwriting has been accomplished. When you're done, you'll need to reinstall the operating system because there won't be a trace of it on your hard disk.

WipeDrive meets a U.S. Department of Defense standard for sanitizing disk drives. Not all of the products sold for this purpose are this rigorous. It works on all file formats for PCs, including FAT16, FAT32, NTFS and Linux.

Before you donate your computer, sell it, or send it to the recycler, be sure that it won't be taking a record of your personal and business information with it that might be recovered even years later. Use a serious disk wiping program like WipeDrive for about $40 and you'll have peace of mind that your files won't be coming back to haunt you. For larger organizations, WipeDrive PRO will sanitize serial ATA drives plus SCSI and RAID servers.

Of course, if your disk drive has failed, this program won't help. Skilled identity thieves may still be able to access the platters in your drive and recover the data. Why take the chance? You can disassemble the drive case and smash the magnetic discs inside. I've also heard of people taking an electric drill and drilling holes through the case into the drive platters before tossing the drive into the trash.

Macintosh users will need a disk wiper designed especially for Macs, such as Jiva SuperScrubber.

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