Erase Hard Drive Options – Comparing Formatting Versus Data Cleansing Tools

by Rod Dunne on November 9, 2010

in Articles, Registry Cleaners Articles, Tips and Tools

Erase Hard Drive Options – Comparing Formatting Versus Data Cleansing Tools
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You can erase hard drive data from a PC by formatting the disk or using disk cleaning applications. This article takes a look at both approaches to clarify the security implications of each and which is best used simply for PC maintenance.

Secure erase hard drive software recommendations

Introduction: How files are stored and subsequently erased

When you save one of your documents to disk it is stored as numerous data clusters around the hard drive memory. In addition, the file allocation table (FAT) contains the references of all documents on the disk along with the addresses of their associated clusters.

In the normal course of events, deleting a file leaves the clusters intact but alters the files reference in the FAT to remove any folder attributes (i.e. so that the document no longer appears in Windows Explorer). However, even using basic data file recovery software makes it possible to read the hard drive memory, locate the clusters and piece them back together to find lost files.

How to completely erase hard drive data

You can only securely erase hard drive contents by using data cleaning applications (see recommendations above). These products all work in the same way by repeatedly overwriting the clusters on disk so that file recovery tools cannot be used to reconstitute the files.

When picking a tool, it may be desirable to select one that is capable of selectively overwriting files in order to leave operating system programs and documents intact. This means your computer can be used immediately without having to reinstall the operating system, safe in the knowledge that your personal information has been overwritten.

Why formatting does not secure erase hard drive contents

By comparison, using formatting utilities (e.g. Windows provides one in their emergency boot disk) are actually quite basic and do not completely erase hard drive data. Formatting a drive will simply remove all document indexes from the file allocation table but will still leave the clusters intact on the disk (i.e. the actual contents of your files).

The one other thing that a formatter does is flag these clusters as available to reuse (to the operating system) for storing any new documents to the disk. In essence, this does mean that the formatted files/clusters will eventually be overwritten as new applications are installed and new information is stored to disk.

However, many data recovery tools could simply read these clusters quite easily and allow the user to copy them back to a directory. With this in mind, formatting utilities should really only be used as part of PC maintenance when reinstalling/upgrading the operating system as an effective way to clear out operating system configurations.

Erase hard drive software – Recommended Tools:

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