How to Securely Wipe a Hard Drive

Securely Wipe Hard Drive

How To Securely Wipe A Hard Drive to Protect Your Data from Identity Theft

When you need to wipe a hard drive, you must protect your data so no one can access anything left over on. Our computers contain a ton of personal and work-related information – passwords, bank account logins, ID numbers, and tax records – which are all at risk. If someone to find your old hard drive and read the data, they could steal your information which could result in identity theft. Even though you erase the files, anyone with basic computer skills can read the data on it if it is not wiped clean, after it’s removed from the computer. To destroy your data safely and securely, you must complete wipe the data or destroy the magnetic platters inside.

Erase and Overwrite Drives

Download an Hard Drive Eraser App

Disassemble Hard Drive to Physcially Destory It

It’s important to understand how hard drives and file systems work so you can choose a method to wipe your hard drive that works best and is secure. Computers store data on hard drives by writing data magnetically to the storage device in chunks called sectors. When a file is written, the computer also saves the location of the file in a directory listing table. The file may or may not be stored in contiguous sectors making the directory table very important. When you open a file or app on your computer, your operating system checks the directory table for the location of the requested files and then retrieves them.

Backup Your Data Before You Begin

Back up your data before you attempt to wipe your hard drive. Often, we think we have everything moved to a new laptop or saved on cloud storage, but find that months later, we need something from the old drive. This happened with my taxes. I thought I had everything backed up but when it came to annual tax returns, I needed to go back to my old laptop for several years of tax forms.

hard drive

Can You Completely Wipe A Hard Drive?

Windows computer users can securely wipe a hard drive, but they will need some software to help, erase and overwrite all sectors, or physically destroy the hard drive.

Does Removing Hard Drive Remove All Data?

Removing a hard drive from a desktop computer or laptop does not remove all the data. Removing a hard drive just removes the physical drive itself. The data remans on the hard drive as it does not need electricity or to be attached to a computer to be saved. The hard drive or SSD can be easily popped into another compatible computer and your data compromised.

Erase Hard Drive Files

Erasing hard drive files is not a secure way to wipe data. Erasing files is a good start but it doesn’t accomplish what most people think. When you erase files, your computer’s operating system simply removes the files name and location from the directory table. In other words, the files are still on there, it’s just that your computer doesn’t know what sector the files are located in.

There are utilities available that automatically reconstruct the hard drive’s directory and then get to your files. Sometimes the directory tables on a hard drive become damaged and your computer loses the ability to access those fields because it does not know where the files are anymore. These hard drive recovery apps help hackers restore your tables and sectors.


Does Reformatting A Hard Drive Erase It?

Reformatting your hard drive is more secure than just erasing files but reformatting a hard disk or SSD does not erase the data on the disk permanently. This process only the erases the disk sector address tables themselves. Even after reformatting, all your data is still on the hard drive, but your computer doesn’t know what sector the files are located in because the directory table are gone.


CHKDSK is a Windows system process that scans the selected hard drive and verifies the file system integrity of a volume and fixes logical file system errors. When you run CHKDSK, you also can optimize and regain fragmented hard drive space. When you choose to defragment your hard drive, the utility will move file fragments physically close to each other on the hard drive. During this process, files are being moved and old sectors are overwritten. This can help with securing deleted files. However, it is not the same as wiping out the hard drive and is no guarantee that the data you want to erase is gone permanently.

Erase and Overwrite Drives

If you have more than a drive’s worth of data and images, you can erase, reformat, and fill up your hard drive yourself.

  1. Backup your data
  2. Erase all Files
  3. Reformat your hard drive
  4. Run CHKDSK
  5. Then overwrite all the space on your hard disk
  6. Erase everything and reformat again

Download an Hard Drive Eraser App

There are many tools available to wipe out the data on hard drive. Most cost money and are available online. Be sure to select a quality tool and read reviews so you are not downloading malware on accident. Data erasing tools usually work by erasing then filling up the hard drive with new data to fill it up to make sure that all sectors are overwritten.

Disassemble Hard Drive to Physcially Destory It

Destroying a hard drive manually is a cheap way to wipe all your data. There are several methods to destroy hard drives and flash drives. When using physical destruction, you must make sure your expose and damage the platers within the hard rive casing. Using a strong magnet or puncture or cut of the internals storage platters. Hammering and drill presses work well too!

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Michelle writes about cyber security, data privacy focusing on social media privacy as well as how to protect your IoT devices. She She has worked in internet technology for over 20 years and owns METRONY, LLC. Michelle earned a B.S. in Engineering from Rensselaer Polytechnic Institute. Michelle published a guide to Cyber Security for Business Travelers