How Delete All Data From The Computer or Hard Drive

Operating system and data are stored on disk drives. The rule of thumb says that you should run your operating system (Windows or macOS) on SSDs (Solid State Drives) instead of on HDDs (Hard Disk Drive). SSDs are faster, more reliable, and they run silently. In almost all cases that you can see, the operating system is installed on the internal disk drive. There are certain cases where Windows can be also installed on USB flash drives using Windows To Go technology. But that is not part of our article today.

There are also external disk drives. They are portable storage devices typically used to store personal or business data or store a backup copy. You connect them to your Windows or macOS machine using the USB connection. The example of both, internal and external disks are shown below.

How Delete All Data From The Computer or Hard Drive

 

Title: (Left) Internal WD 500 GB disk and External SanDisk Extreme Portable SSD 1TB (Right)

 

You probably had or will have a situation where you need(ed) to wipe data from your computer, laptop, or external storage device. Maybe you wanted to wipe the data you don’t need anymore or you want to borrow or sell your machine or external disk drive to someone else, and you don’t want that someone can access or read your data. When it comes to the system disk (Windows and macOS), you can’t just format them because it contains the operating system you are using. Formatting that volume could cause your computer to stop working. The procedure is done in a bit different way we explain in the coming section. Both, Windows and macOS, include native tools for formatting your disk drives.

Wipe data from Windows system disk

Imagine a scenario where you want to reinstall or upgrade your Windows to a newer operating system. Or you maybe want to borrow or sell your machine to someone else. In both situations, during the Windows installation procedure, you can wipe the data from disk drives. So, how does it work?

When you boot your machine using Windows image, you can install Windows in two ways. The first one is by wiping all the data from the disk drive and then installing Windows on it. This is the most common and safest option.

For the sake of sharing, the second option is to install Windows on the disk drive without deleting the old Windows and data. In this case, the old Windows and data will be moved to a directory called Windows.old (located within C:\). This is something you don’t want to do if you want to delete your data.

By following common sense, we will show you how to wipe the data during the Windows 11 installation procedure. However, this procedure is equally applicable to the previous Windows operating systems. When you boot your machine using Windows 11 or another Windows boot disk, please do the following.

  1. Select the language, time and currency, and keyboard, and then click Next.

How Delete All Data From The Computer or Hard Drive

Title: Windows Setup

  1. Click Install Now.
  2. Accept the Microsoft Software License Terms and click
  3. Select Custom: Install Windows only (advanced).

 

How Delete All Data From The Computer or Hard Drive

Title: Choose the installation type

  1. Windows will list all available disks and partitions. In order to wipe the data from the disk, you need to delete or format all the disks by selecting each of them and clicking Delete or Format. If you skip this step and you click on Next, the old Windows and data will not be deleted, but moved to C:\Windows.old.

How Delete All Data From The Computer or Hard Drive

Title: List of available disks and partitions

 

  1. Once you delete or format all the disks and partitions, it should list only a single disk (if you delete partitions) as shown in the screenshot below. After that, you need to click New to create a new partition and proceed with the installation. The complete installation is not a part of this article, but the only explanation on how to wipe the data which we covered.

 

How Delete All Data From The Computer or Hard Drive

Title: Create new partition(s) and click Next to install Windows

Wipe data from macOS system disk

The story with macOS is the same as with Windows. During the installation process, you should format your disk and install macOS on it. Once you boot your machine using bootable macOS installation media, you need to follow the procedure below.

  1. Configure language and accept the software license agreement.
  2. Select Disk Utility and click
  3. On the left side select the disk drive and then click on Erase tab in the middle of the menu.
  4. Define the name of the disk, choose the format and scheme and click

How Delete All Data From The Computer or Hard Drive

Title: Erase disk

  1. After formatting the disk click on Done and close the Windows.
  2. Continue with the installation procedure.

Wipe the data from internal and external disk drives

If you want to wipe the data from an internal (non-system disk) or external disk, you can easily do it using the quick or full format in Windows and Disk Utility in macOS. When it comes to Windows, you need to connect your external disk to a computer or laptop and follow the instructions below. The procedure applies to all Windows operating systems.

  1. Open This PC (former My Computer in Windows 7).
  2. Right-click on the internal non-system or external disk and choose.
  3. There are two options available, quick and full format. The difference between them is that quick format only delete the data, and full format deletes the data and check for the bad sectors. As it does more work, the full format takes longer. We do recommend you do a full format as it is the safest thing to do.

How Delete All Data From The Computer or Hard Drive

Title: Full format

  1. You can now access your disk and verify if it is empty.

How to do it on macOS?

If you are running macOS, you can format your internal (non-system) and external disk using Disk Utility. Please follow the procedure below.

  1. Open Disk Utility.
  2. Select your disk drive on the left side of the window and click on Erase tab in the middle of the menu.
  3. Click on Format.
  4. Once the procedure is done, you can access and verify if your disk is empty.