Definitely encouraging this; I would've recommended it in my first post, but figured I'd help him troubleshoot first. Though using "chntpw" is the best tool, especially it's easy enough to get in any nearly any Linux distro if you don't want to have a CD dedicated to just that.
Making a password reset disk has always seemed like a bad idea to me, because it's a piece proprietary software/tool kit and I'd like to know what exactly is going on when I aim to grab a client's password for reset.
It is Windows 10 64 bit. I download and install chntpw, but i can't find any account. I booted the disk from another computer running Windows 7, it worked fine. so weird. Tried another program and bypass the password with the app. Make sure UEFI is disabled during boot.
First and foremost, to make sure we are on the same page, you downloaded and burned chntpw to either a flash drive or CD. Second, there is sometimes a bit of issue with the program as it can't always identify users, but I believe if you use the command it will list users and with the -u you can reset the password that way. Also, you may have the ability of activating the built-in Administrator account to reset it that way. If you have any more questions, just keep posting, we're here to help!