Securely Wiping Data From Old Drives

By Author: Nash Owens
Total Articles: 7
Comment this article

Much of the time we computer users are concerned with keeping our files intact. It's easy to go into a panic when important data goes missing on our hard drives. Much has been written about keeping routine backups of computer files to guard against data loss. Even so, many users still don't backup their important files. This includes home and casual users and business owners as well. However, the topic of this article is not file recovery, but destruction. There are some cases in which the complete removal of data can be as crucial as recovery. Here are a few examples:

• When replacing a small hard drive with a larger one, especially if the old drive is to be trashed, sold or given away

• When replacing an old computer with a new one

• When giving an old computer away or selling it

• When throwing away a broken computer that still has an intact hard drive

Deleting a file from a hard drive does not guarantee complete removal. In fact, only certain location and access information is removed during deletion. The content of ...
... the file still exists until the file is completely overwritten. The deletion process marks the file's location on the hard drive as available. However, the data may not be overwritten for some time. As long as the content of the file is still present, the file can possibly be retrieved.

That's why it so important that in the examples above that the hard drive is wiped. Drive wiping is a more intensive process that ensures that any files and other data cannot be retrieved by data recovery software. The goal is preventing unauthorized access or identity theft.

A wipe can be done on the entire drive, removing all data, files and programs from the drive including the OS. However, wiping only the portion or partition where user data is present preserves the OS and programs. A wiping program that runs from a bootable disk is able to do a more complete job.

Most operating systems do not include a program for wiping a drive. Third-party software is employed in the wiping process. The program overwrites the data, often several times, to ensure that the contents have been removed. The best programs will check to verify that all data has been destroyed by overwriting.

There are data destruction programs that will work with several drives at the same time. Each drive's progress is tracked and the operator is notified of completion, possible errors and other information. In a hot-swappable configuration, a drive that is wiped can be removed and another put in its place.

Whether working on a PC or a Mac, deleted filecontent and directory structure is completely overwritten, ensuring that your data cannot be retrieved by anyone and used maliciously.