http://www.howtogeek.com/96630/how-to-reset-your-forgotten-windows-password-the-easy-way/
booting to repair and using command prompt
copy c:\windows\system32\sethc.exe c:\
copy c:\windows\system32\cmd.exe c:\windows\system32\sethc.exe
Once you get to the login screen, hit the Shift key 5 times
net user "user name" 'MyNewPassword" (without quotes)
or
kon-boot
cmd admin
netuser to find name
netuser
hit enter twice
if not work
linux
system32
utilman.exe rename to old
copy cmd.exe to linux desktop
rename to utilman.exe
copy to system32
boot to windows
do the same as in kon-boot
change password or delete by hiting enter twice
back to linux and restore utilman.exe.old to original
video
http://www.youtube.com/watch?v=LYi-ZfZCVJg