Hello, this is Emily.
If you are not running terribly low on free space on the system drive, you can do the following to do the factory reset:
Hold down shift key while you choose the Windows restart option. Then go to Troubleshoot > Reset this PC. Choose the option that deletes everything.
However, if you are low on free space, you will have to do the following to perform a clean install:
To perform a clean installation of Windows 10 using the Windows Media Creation Tool. You do need to get access to another computer so you can download the Windows installation files into a flash drive, then use the flash drive to help your computer. Hopefully you have a spare computer, or you can have friend or family help you.
The following steps should be done on a working Windows computer:
Download the Windows Media Creation Tool from Microsoft's official website. https://www.microsoft.com/software-download/win...
Run the tool and select "Create installation media for another PC."
Choose your language, edition, and architecture (32 or 64-bit) and select "Next."
Choose "USB flash drive" as the media to use for the installation and select "Next."
Connect a USB flash drive with at least 8 GB of free space to your computer.
Select the USB flash drive you want to use, and then select "Next."
The tool will then download the required files and create the installation media.
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Now these steps will be done on your problematic computer:
Go to the computer's BIOS boot menu to have it boot from the USB drive.
Follow the on-screen instructions to install Windows 10, making sure to choose "Custom install" and select the option to delete all existing partitions.
Once the installation is complete, you'll have a clean installation of Windows 10 on your computer.