Step 1. Back up the data on the hard drive
Although the process of formatting a Windows 10 computer can be done very easily, the changes that are applied after formatting are permanent. You will delete all applications, settings, and personal data, and reinstall Windows from scratch. Fortunately, you can also easily back up your data using the tools included with your computer's operating system. Try searching and reading articles on how to back up files on Windows 10 on wikiHow to learn the procedure for backing up data to a DVD, CD, external hard drive, or cloud service.
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Step 2. Open the Windows settings menu (“Settings”)
This gear icon appears in the “Start” menu.
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Step 3. Click Update & Security
This option is indicated by a two curved arrow icon.
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Step 4. Click Recovery
This option is in the left pane.
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Step 5. Click the Get started button under "Reset this PC"
This option is the first button at the top of the right pane.
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Step 6. Click Remove everything
This option is the second option on the blue screen.
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Step 7. Click Remove files and clean the drive
This option is the second pick. You will need the option to format the hard drive because the other options only work to empty and reinstall the operating system, without formatting the drive.
- Drive cleaning is an important procedure if you plan to sell or give away your computer. This is because formatting a hard drive would make it difficult for someone with malicious intent to recover deleted files. However, if you want to keep your computer, you can click “ Just remove my files ” to skip the drive formatting process.
- Another, more serious option for freeing the hard drive is to use a third-party data cleaning tool such as DBAN (Darik's Boot and Nuke). If you're using a drive-emptying program, make sure you have a Windows 10 recovery drive or DVD available so you can reinstall the operating system. Try searching and reading the wikiHow article on how to free your hard drive to learn more about this option.
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Step 8. Click Next on the warning page
If you see a message saying that your PC's operating system has been upgraded to Windows 10, this means that reinstalling Windows prevents you from switching to a previous version of Windows.
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Step 9. Click Reset to format the computer
This process can take some time (a few minutes to several hours), depending on the size and speed of the hard drive.
If you are using a laptop, make sure you connect the device to a power source so that the formatting process is not interrupted
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Step 10. Click Continue after formatting is complete
Your computer is now finished formatting. If you want to reinstall Windows, follow the prompts that appear on the screen.
Method 2 of 3: On Windows 8.1
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Step 1. Back up data
Since the process of formatting your computer will erase all data and settings, you may need to back up your data first. Search and read the wikiHow article on how to back up data on a Windows computer to quickly learn the computer backup procedure before you move on to the next step.
If your computer originally came with Windows 8 operating system instead of Windows 8.1, formatting and resetting your computer will take you back to Windows 8. But don't worry. You will be prompted to install the free upgrade to Windows 8.1 after the main operating system is installed
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Step 2. Move the cursor to the lower right corner of the screen
The “Charms” menu will open.
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Step 3. Click “Settings”
This gear icon is in the “Charms” menu.
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Step 4. Click Change PC Settings
This option is at the bottom of the menu.
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Step 5. Click the Update and recovery tab
This tab is at the bottom of the left pane.
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Step 6. Click Recovery
This option is in the right pane.
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Step 7. Click Get started under the “Remove everything and reinstall Windows” segment
It's in the middle of the right pane. Make sure you don't click " Get started " on different segments as this panel creates multiple segments.
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Step 8. Click Next
With this option, you confirm the deletion of all files, applications, and settings and the computer.
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Step 9. Select the drive you want to format
If you only need to format the drive that was selected as the installation location for Windows 8, select “ Only the drive where Windows is installed To format all drives on the computer, select “ All drives ”.
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Step 10. Click Fully clean the drive
This option (the second option) ensures that the drive is completely formatted.
- If you're planning to save your computer and aren't worried about people being able to access your deleted files, click “ Just remove my files " The drive will not be formatted with this option.
- Another, more serious option for freeing the hard drive is to use a third-party data cleaning tool such as DBAN (Darik's Boot and Nuke). DBAN and similar tools make it impossible for others to find fragments of files that have been deleted, so they are useful if you plan to sell or give away your computer. Just make sure you have recovery media so you can reinstall Windows afterwards. Search and read articles on how to free your hard drive to learn more about this option.
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Step 11. Click Reset to format the computer
This process can take some time (a few minutes to several hours), depending on the size and speed of the hard drive.
- If you are using a laptop, make sure you connect the device to a power source so that the formatting process is not interrupted.
- After formatting is complete, the computer will restart and you will be prompted to reinstall Windows. Follow the on-screen instructions if you wish to reinstall the operating system.
Method 3 of 3: On MacOS
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Step 1. Back up data
Formatting your computer will erase all data so make sure you have backed up any content you want to keep. Read the article on how to back up data on a Mac to learn how to save files to Time Machine or iCloud.
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Step 2. Turn on the computer and press Command+R
If the computer is on, restart the computer and press the key combination as soon as the computer restarts. Recovery mode or Recovery Mode will load afterwards.
You can release your finger from the button once you see the Apple logo or the initial loading page
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Step 3. Select Disk Utility
This is the last option in the " macOS Utilities " window.
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Step 4. Click Continue
It's in the lower-right corner of the screen.
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Step 5. Click the View menu
It's in the menu bar at the top of the screen.
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Step 6. Click Show All Devices
All disks connected to the computer will load in the left pane.
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Step 7. Select the disc you want to format
For example, if you want to format the primary drive that has MacOS installed, select the first disk at the top of the list (under the "Internal" section).
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Step 8. Click the Erase button
It's in the top-center of the window.
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Step 9. Select the formatting details
- “Name”: Enter a name to identify the hard drive.
- “Format”: Leave the option “ APFS ” remains selected as the primary format of the internal hard drive, unless you have a reason or other need.
- “Scheme”: Select “ Choose GUID Partition Map ”.
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Step 10. Click Erase to format the disc
You will be asked to verify your Apple ID or password. Once the disc has been emptied and formatted, you will be taken back to the “Disk Utility” list.
If you have multiple additional hard drives, you can format them at this point using Disk Utility
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Step 11. Close the Disk Utility window
You can close it by clicking the red circle in the upper-left corner of the window.