Three Utilities to Delete Your Hard Drive Before Discarding Your Computer

Before I discard my old computer or any of the drives, I like to run a deletion utility to ensure that someone cannot retrieve any old data from my hard drive. This is especially important when there might be personal or financial data. Just like shredding our personal documents before tossing them in the trash these utilities will shred the drives electronically and prepare them for discard or donation. So when you are done you know that you can safely donate the hard drive to a local charity or hardware donation location. Which as a side not I think is a good idea. There might be a little life left in the hard drive why not let someone less fortunate take advantage of your excess. I encourage everyone to donate old equipment.

What do these utilities do and how does this protect one's old data on the drive from being recovered. As your files are being stored on your hard drive a part of the drive called the File Allocation Table is updated telling the system where the file is located. Think of this item like the old card catalog system in the library. If you were looking for a book, the catalog system would tell you that such and such book was located at location "X". Well the File Allocation Table works the same way for your hard drive. It says that file 'X" is located at sector "x". When you delete a file, the system does not actually remove the file. Instead, what the system does is tell the File Allocation Table that sector "x" is free. So using the library as an example one would think that the system would go over and take the book off the shelf and then throw it away, but instead it just tell you the spot is empty. So like the library if you were to walk over to that shelf you would find the book.

To be efficient our computer system don't erase the file. They just wait till you save another file and then uses the space that you just deleted a file from and places the new file there. So all the computer has to do is update the File Allocation table telling itself that file "y" now lives there. This produces a problem because what if the file that being saved is not the same size, perhaps it is a smaller file, well there will be remnants of the old file still there. However, what if I undid the change to the File Allocation Table? Suppose I went back to the old File Allocation Table and restored the file? Could I then piece together the information? Yes I could, and that is what File restoration utilities do.

A good example would be writing on a piece of paper. You write a letter to a family member. Then you go back and erase a sentence, and re write the sentence. Well chances are you will see the remnants of the original sentence under the newly written one. Well if you can see part of what was originally written you might be able to determine what the original sentence was. Recovery software does this electronically. The software will find remnants and then it will do its best to deduce what was originally there. If there are enough little pieces it can piece together the original file and now that tax file that you thought was deleted is in someone else's hand and they have your social security number, address, etc.

When writing that letter you found that you needed to erase a sentence, but you want to make sure that no one would be able to see it, so you erase it, then you draw shapes and letters over the entire line repeatedly until no one can make out what you wrote. This is what hard drive erasing software does to your hard drive. It goes out and writes random characters sector by sector until all spaces on the hard drive are full, then it clears the File Allocation Table (telling the system that the drive is empty) and does this again and again several times until it is certain that one cannot find any remnants of any old files. This is successfully destroying the data on the drive and attempting to recover data impossible. Once done the drive is clean of data and is still operable for use.

Therefore, had you donated that drive your data is not on the drive, but someone can safely use the drive in his or her computer, thus giving it new life. Here are examples of three different programs that can help erase/clean your drive of any old data and prepare it for donation.

One product that is free to use is Hard Drive Eraser. The utility does incorporate the DoD (Department of Defense) 5220-22m standard algorithm. This software works only on Windows Operating Systems. It will work on FAT, FAT32 and NTFS partition types and has an advanced algorithm for erasing the drive.

Blancco offers a variety of products to erase your hard drives. The different options available are:

• Data Center

• Server

• PC

• Flash Media

• SPARC

This company also have a version called File Shredder. This utility will safely dispose of a single file. Therefore if you want to ensure that a specific file or files are not recoverable, this utility will delete the file(s) and then write over the space. This is helpful as it does not destroy the entire hard drive, but it deletes a file 100%. The File Shredder utility costs about $35.00 and the PC edition is $32.00. The server edition costs $110.00, but works on RAID drives and deletes everything on a RAID set.

I like Killdisk because not only does it delete your drive with the DoD 5220.22m format, but it also works with DOS, and it can clean areas of the drive that are not in use without destroying the good areas of your drive. The company offers a free version as well as a professional version. The Pro version costs around $59.95. The more licenses that you buy the more discounted the software. This software also supports all drive types, SSD, IDE, SDCSI, SATA and works with all partition types and even large drives. It has such a small file that the entire utility can fit onto a floppy disk.

So now that you know where to go to get one of several utilities to clean your drives of personal information go and delete those files, clean those drives then donate them to be used again so we can have a greener earth.