Win 8.1 and 10 Password Reset/Removal
Boot with a recovery disk or USB
Shift + F10 to open a command prompt
Run these commands
move c:\windows\system32\utilman.exe c:\windows\system32\utilman.exe.bak
copy c:\windows\system32\cmd.exe c:\windows\system32\utilman.exe
wpeutil reboot
Now on the login screen the utility manager will open a command prompt
Run these commands
net user <username> /add
net localgroup administrators <username> /add
Run these commandsClose prompt and reboot. Your new user will be in the login screen.
Alternate for Windows 10
Boot to install CD go to command prompt
X:\Sources
C: <enter>
Cd system32 <enter>.
You should be at C:\Windows\System32
Run these commands
rename osk.exe osk.old <enter>
rename cmd.exe osk.exe <enter>
Exit <enter>
Boot to hard drive
The On Screen Keyboard will now launch a command prompt
Cd c:\Windows\System32
Net user <displays user accounts>
Net user <user> * to reset local account pw
To put the command prompt back boot to the install CD
Back to command prompt, c:\Windows\System32
Rename osk.exe cmd.exe
Rename osk.old osk.exe