If you can at least access root, then try the following...

All user encrypted passwords are stored in /etc/shadow file. The quick way to remove/delete a user password is pass --delete option to passwd command. First, login in as a root user.
Command to delete user password under Linux Type the following command to delete a user password:
# passwd --delete username
OR
# passwd -d username
Above command delete a user's password (make it empty). This is a quick way to disable a password for an account. It will set the named account passwordless. User will not able to login. It is also a good idea to setup user shell to nologin to avoid security related problems:# usrmod -s /sbin/nologin usernameFor example to delete password for user sweta, Type:# passwd -d sweta
# usrmod -s /sbin/nologin sweta

Try to remove it with Windows Password Recovery Tool 3.0.
It works perfectly to reset any local user account to a blank password. I Wrote it to an old 128mb USB flash drive do this. Booting up and clearing a password takes a minute or two works like a charm. Source(s): http://search.yahoo.com/search;_ylt=A0oG…