You could use pspasswd from sysinternals tools.
usage: pspasswd [\\computer[,computer[,...] | @file [-u username [-p password]]] Username [NewPassword]]
Run the command on the computer or computers specified. If you omit the computer name the command runs on the local system and if you enter a computer name of
\\* then the command runs on all computers in the current domain.
Execute the command on each of the computers listed in the file.
Specifies optional user name for login to remote computer.
Specifies optional password. If you omit this you will be prompted to enter a hidden password.
Specifies name of account for password change.
New password. If ommitted a NULL password is applied.