The procedure for restoring or resetting a computer to factory settings is ideal for people looking to reinstall an operating system or sell a computer to another person. The reset process varies depending on the computer model, manufacturer, and operating system.
Steps
Method 1 of 4: Windows 10

Step 1. Make a copy of all personal files and save them to an external drive, flash drive, or cloud storage
Resetting your computer will delete all personal files and data from your device.

Step 2. Click on "Options" and select "Update & Security"

Step 3. Select the "Recovery" section and click on "Start"

Step 4. Select one of the options presented
On Windows 10, you can reset and keep your files, delete all files, or restore your device to factory settings.
- Keep my files: Reinstalls Windows 10 while keeping all personal files. Applications, drivers, and installed or changed settings will be removed.
- Remove All: Reinstalls Windows 10 and removes all files, applications, drivers, and installed or changed settings.
- Restore to factory settings: Installs the original version of Windows that came with your computer. All files, applications, drivers, and installed or changed settings will be removed.

Step 5. Follow the instructions on the screen and reset your computer
When the reinstallation is complete, the start-up screen is displayed.
Method 2 of 4: Windows 8.1 / 8

Step 1. Make a copy of all personal files and save them to an external drive, flash drive, or cloud storage
Resetting your computer will delete all personal files and data from your device.

Step 2. Click on "Options" and select "PC Settings"

Step 3. Select the "Update and Recovery" section and click on "Recovery"

Step 4. Click on the "Get Started" button in the "Remove All Data and Reinstall Windows" section

Step 5. Follow the instructions on the screen and reset your computer
When the reinstallation is complete, the start-up screen is displayed.
If you upgraded your operating system to version 8.1, resetting your computer will restore Windows 8. After that, you will have to upgrade your operating system to version 8.1 again
Method 3 of 4: Windows 7 / Vista
Step 1. Make a copy of all personal files and save them to an external drive, flash drive, or cloud storage
Resetting your computer will delete all personal files and data from your device. Step 2. Restart your computer, and then wait until the computer detects a command that opens the Advanced Boot Options menu.
The specifics of running the command depend on the model and manufacturer of the computer. On Dell computers, for example, you need to press the F8 key, while on HP computers you need to press the F11 key.
Alternatively, you can insert the operating system installation disc into the drive, go to Control Panel> Recovery> Advanced Recovery Methods and select the option to reinstall Windows from the installation disc. The system will guide you through the process of resetting and reinstalling Windows
Step 3. Press the key that opens access to the Advanced Boot Options menu or the Recovery menu. 4 Click on the option to perform a system reset or restore
Depending on the model and manufacturer of your computer, these options may have different names on Windows 7 and Windows Vista. Look for something similar to Restore to Factory Settings. Step 5. Follow the instructions on the screen to reset your computer.
As a result, you will find yourself on the start screen and the computer will be restored to factory settings.
Method 4 of 4: Mac OS X

Step 1. Make a copy of all personal files and save them to an external drive, flash drive, or cloud storage
Resetting your computer will delete all personal files and data from your device.

Step 2. Open the Apple menu and choose Restart

Step 3. After rebooting, a gray start-up screen will appear on the screen
When this happens, hold down the Command + R keys. After that, the recovery menu will appear on the screen.

Step 4. Select "Disk Utility" and click "Continue"

Step 5. Select the boot or hard drive you want to reset on the left panel of the utility, and then click on the "Erase" tab

Step 6. Select Mac OS Extended (Journaled) from the Format drop-down menu

Step 7. Enter a name for the disc and click "Erase"
The system then proceeds to erase all data and format the hard drive, which may take several minutes.

Step 8. Click on "Disk Utility" and select "Exit"
This will close the Disk Utility window.

Step 9. Click on "Reinstall OS X" and then click "Continue"

Step 10. Follow the instructions on the screen and reinstall the operating system
At the end of the process, the computer will be restored to factory settings.