I wouldn't trust a reset. You need to wipe the HDD (DON'T WIPE AN SSD!!!!) and do a clean install of Win10. There are other things you might do, but the only correct one is a wipe and clean install.
Use DBAN Disk Wipe for the wipe. (https://dban.org/)
This tells you how: http://www.techfleece.com/2013/08/22/how-to-securely-wipe-your-hard-drive-using-dban/
I wouldn't trust a reset. You need to wipe the HDD (DON'T WIPE AN SSD!!!!) and do a clean install of Win10. There are other things you might do, but the only correct one is a wipe and clean install.
Use DBAN Disk Wipe for the wipe. (https://dban.org/)
This tells you how: http://www.techfleece.com/2013/08/22/how-to-securely-wipe-your-hard-drive-using-dban/
download DBAN (https://dban.org/) into your Downloads folder,
YOU NEED TO MOVE DBAN FROM YOUR DOWNLOAD FOLDER TO A USB USING RUFUS.EXE (http://rufus.akeo.ie/) This tells you how: https://www.wikihow.com/Use-Rufus
then use it to boot the computer (http://www.techfleece.com/2013/08/22/how-to-securely-wipe-your-hard-drive-using-dban/). You can wipe the C:\ drive from there.