I absolutely hate microsoft products thats why I love breaking it. This hack, is way too easy. Whatever your reason for changing any users password, this simple howto will surely satisfy that need. The only way to prevent this currently is with full disk encryption. Here is how you change windows password within Ubuntu Hardy Heron.
You can either use your livecd or hdd
sudo apt-get install chntpw
Now its installed, so lets get to work...
Ok I am assuming your using a hardy heron livecd or a Ubuntu Hardy Heron full install
You will now need to mount the windows partition read/write permission then navigate to %systemroot%/system32/config
Once your located in the config directory issue this command to change the password
chntpw -u administrator SAM
- Prompt for password for 'administrator', if found (otherwise do nothing) use * to blank
Now reboot and login to winblows
Optionally you can skip resetting the password and just install Ubuntu