How do I securely wipe my external hard drive?

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How do I securely wipe my external hard drive

Why You Should Wipe Your External Hard Drive

There are several important reasons to securely wipe your external hard drive before disposing of it:

Protect your data – Wiping the drive removes all your personal files and prevents sensitive information from falling into the wrong hands if the drive is lost, stolen, or recycled. Even deleting files normally just removes pointers to the data, allowing it to be recovered.

Prevent identity theft – An external hard drive contains a trove of personal data like financial records, IDs, and passwords that criminals could leverage for identity theft or fraud if obtained. Wiping prevents this.

Resell the device – You can get more money selling your used external hard drive if you wipe it first, as the next owner doesn’t want your data. Wiping gives them confidence the drive is clean and ready for their own use.

Safely recycle the device – Wiping also ensures no residual personal data remains if you’re recycling the hard drive responsibly through an electronics recycling program.

Delete all your data permanently – Hard drive wiping provides a way to completely obliterate data so it is unrecoverable. This gives you peace of mind nothing is left over when the device changes hands.

What Securely Wiping Means

Securely wiping an external hard drive is different from simply deleting files or formatting the drive. When you normally delete files or format a drive, the data itself is not actually erased from the physical drive. The files are simply marked as deleted in the file system, and the space they occupied is made available to write new data. The original data still remains on the physical drive and could potentially be recovered.

Secure wiping involves overwriting the actual raw data on the drive to make recovery impossible. Special software is used to overwrite the drive with random data, not just once, but multiple times. The more passes of overwriting that are done, the more secure the wiping process is. Typically 3-7 passes are recommended for securely wiping a hard drive.

This overwriting process scrubs the data at the lowest level to ensure no traces are left behind. The aim is to prevent even advanced forensic data recovery methods from being able to recover or reconstruct any deleted files or partitions.

When You Should Wipe an External Drive

There are a few key times when it is crucial to securely wipe an external hard drive before parting with it:

Before selling or giving away the drive

If you plan on selling or giving your external drive to someone else, you’ll want to wipe it first. This ensures no personal files or confidential data remains that the next owner could access. Formatting or deleting files using your operating system’s tools is not enough, as data recovery software could potentially restore them. Secure wiping removes all traces of data.

Before recycling or disposing of the device

Drives disposed of or recycled without being wiped can lead to identity theft if someone recovers the data. Studies have found large numbers of drives resold or disposed of still contain sensitive financial records, medical info, and other private data. Wiping the drive prevents this.

If the device has been lost or stolen

If your external drive goes missing, you should immediately wipe it using cloud-linked device management software if possible. This removes the data remotely in case the drive ends up in the wrong hands. If you don’t have a remote wipe option, physically destroying the drive may be your only recourse if recovered.

The key point is that anytime a drive leaves your possession, wiping provides an extra layer of protection against potential data leaks.

Choosing Software to Wipe Your Drive

There are several disk utility tools available to securely erase external drives. Some popular options include:

The main factors to consider are effectiveness at secure wiping, ease of use, and cost. Open source tools like Eraser provide a good balance but may require more technical expertise. Paid tools like KillDisk offer greater convenience at the cost of money. Evaluate your needs and research tools to find the best option.

Erasing Specific Files vs Whole Drive

There are two main options when it comes to securely wiping your external hard drive:

  • Erase specific sensitive files and folders on the drive
  • Erase the entire hard drive

If you still plan on using the external hard drive and just want to remove a few sensitive files or folders, then wiping only those specific items is an option. This allows you to keep the rest of the data intact.

Some drive wiping software like Eraser give you the ability to selectively choose files and folders to permanently erase.

However, if you want to wipe the entire drive before disposing of it, selling it, or giving it away, you’ll want to completely overwrite all data. This ensures everything is erased beyond recovery.

Wiping only specific files still leaves trace data behind that could potentially be recovered. Wiping the full drive removes any chance of remnant data being accessed again.

How Long Drive Wiping Takes

Drive wiping can take a significant amount of time depending on the size of the drive and the number of passes specified. For example, a 500 GB hard drive connected via Firewire 800 took over 18 hours to complete a 7-pass secure erase process in one test[1]. The more passes, the longer it will take. For most external hard drives, you can expect the wiping process to take multiple hours.

Some factors that affect total wipe time include:

  • Drive size – larger drives take longer
  • Drive interface – newer interfaces like USB 3.0 are faster
  • Drive type – SSDs can wipe faster than HDDs
  • Number of passes – more passes mean more time

It’s a good idea to start the wiping process before going to bed or leaving the computer for an extended time. Many drive wiping tools will provide an estimate of the total time required. Be sure to verify that the wiping process completed successfully once it finishes.

Step-by-Step Guide to Wiping a Drive

Wiping an external hard drive is a straightforward process that involves just a few steps. Here is a walkthrough for securely erasing an external drive on Windows 10:

  1. Download and install a drive wiping utility like CCleaner. Make sure to download the free version.
  2. Connect your external hard drive to your computer via USB.
  3. Open CCleaner and click on ‘Wipe Free Space’ in the left menu.
  4. Select your external hard drive from the list of available drives.
  5. Click on ‘Wipe’. This will completely overwrite all existing data on the drive.
  6. The wiping process can take several hours depending on the drive size. Let it run until completion.
  7. Once finished, you can close CCleaner. Your external hard drive is now wiped and ready for reuse or disposal.

That’s all there is to it! Just be patient during the wiping process. When done correctly, no data will be recoverable from the drive.

Securely Wiping SSDs vs HDDs

There are some key differences in securely wiping solid state drives (SSDs) versus traditional hard disk drives (HDDs).

With HDDs, the goal is to overwrite the drive with random dummy data multiple times to make the original data unrecoverable. According to Tom’s Hardware, the best practice for HDDs is to overwrite the drive at least 3 times https://www.tomshardware.com/how-to/secure-erase-ssd-or-hard-drive.

SSDs work differently than HDDs, so the same overwrite technique is not as effective. SSDs have wear-leveling algorithms that distribute writes across different blocks of memory. This means overwriting the SSD once may not actually touch all the blocks that contain data.

For SSDs, using the drive’s built-in secure erase command is recommended. This runs a firmware process to reset all memory blocks to their factory state. Some disk utility software also supports SSD secure erasing. According to PCWorld, Parted Magic is one option that works for both HDD and SSD wiping https://www.pcworld.com/article/461014/how-to-securely-erase-your-hard-drive.html.

The secure erase process acts on the entire SSD at once, ensuring no original data remnants are left across any memory blocks. This is the most thorough option for wiping SSDs.

Verifying the Wipe Was Successful

After wiping your external hard drive, it’s crucial to verify that the wipe was successful and no data can be recovered. Here are some methods to check the disk:

On Windows, you can use the native chkdsk utility. Open the Command Prompt as Administrator and type “chkdsk x: /f” where x is the drive letter of your external drive. Chkdsk will scan the drive and confirm if it contains only free space and no recoverable data.

Third-party utilities like Winhex can also be used to visually inspect the raw contents of the drive and confirm all sectors contain zeroes. However, this is a more manual verification process.

You can also boot into a Linux environment like Ubuntu Live CD and use the shred utility to verify the wipe. The command “shred -v -n 1 /dev/sdX” will read every sector and confirm if it only contains zeroes.

For maximum assurance, consider using a professional data recovery service after wiping the drive. Supply them with the drive and ask them to attempt recovering data from it. If they find nothing, you can be certain the wipe was truly successful.

While no method is 100% foolproof, using a combination of the above utilities and techniques can reliably validate that no data remains accessible on the drive after wiping it.

Disposing of the Wiped Drive

After you have securely wiped your external hard drive, you need to properly dispose of it. Simply deleting files or reformatting does not remove all data, so physical destruction is required if highly sensitive data was stored on the drive.

Some secure disposal options include:

  • Using a drill or hammer to damage the physical platters and circuitry beyond repair
  • Taking advantage of Best Buy’s hard drive recycling program, which will shred and destroy drives
  • Finding a local electronics recycling center that provides certified data destruction services

If no sensitive data was present, you can typically recycle the external hard drive. Many local community recycling centers accept old electronics, including hard drives. Just be sure to perform a thorough wipe first.

Regardless of your disposal method, it’s important to remove any sticker labels and make sure the drive cannot be traced back to you. Destroying the drive platters is the most secure option if total data removal is essential.