I was recommended making a Linux booting USB to help me blank the password of a Windows 10 laptop. So I downloaded Ubuntu Live CD and burned it to a USB. boot from the laptop but the utility seems not working. The password is still there after reset.

Would you be able to list the steps you took, after you booted from the live cd, to reset the password?

Here: https://opensource.com/article/18/3/...password-linux

followed the steps exactly suggested in that post and still no luck. However, it is able to remove the password on an old Windows 7 PC

Is the PC booting from UEFI, if yes then it could be the reason.

Or find some tools that can be used for Win 10.

For what it's worth, I have found that on occasion I have needed to use CHNTPW twice in order for it to work.

Boot to Linux USB
run CHNTPW on the appropriate SAM file
enable the account and reset the password
save changes
close CHNTPW
run CHNTPW on the appropriate SAM file
enable the account and reset the password
save changes
close CHNTPW
reboot

I have yet to figure out why it doesn't always seem to work on the first attempt.

Just as an aside - since this tool is modifying a file on the Windows NTFS filesystem, the filesystem needs to be mounted with RW access, and usually it needs to be "clean" (so shutting Windows down nicely, rather than hard powering off).

Is it a local account or a Microsoft account? I don't know if chntpw can unlock a Microsoft account on the local machine.

Most people who use Chntpw are computer savvy,unfortunately, I'm not.I don;t even know much about Chntpw.

If chntpw doesn't work on your Windows 10,try the Ophcrack,as freeware,they do the same thing.
http://ophcrack.sourceforge.net/
https://www.winpwd.com/
By the way,share your a simple method with you.
Using aonther account on this laptop:Go to start button,then click on the control panel and tap on the administrator,the last,now you can delete your password and log into your laptop wihtou/with a new password.

After booting into Ubuntu Live CD, browse to the drive where your Windows 10 was installed. Head into the directory \Windows\System32\ and rename utilman.exe to cmd.exe. When done, reboot and at the login screen you can click on the Ease of Access utility to open Command Prompt with sufficient rights to create a new password for your local admin account.

https://www.technibble.com/bypass-wi...ogons-utilman/
https://www.top-password.com/knowled...eset-disk.html

This method is known to most computer technicians.