to use ADSI for an admin script, you will only need to install it on the admin pc.

ADSI will need to be installed on NT4.0, it comes with w2k.

now having said that you do not need adsi to change a local admin password via a logon script.

you just have to be able to run this command.

code:
shell '%comspec% /c net administrator $password > nul'
with local admin rights.