Secure way of changing 1000 local admin accout passwords.

Hello,

We have 1000 machines that we need to change the local Admin password on. The one thing is it HAS to be done securely no cleartext sent. I know GPO is insecure because the key file is kept in the SYSVOL folder and someone can get at it.

Is there a Powershell script or some other script that someone knows of that can do this??

PS Im a novice scripter

Thanks

D