changing Windows Password [without giving old password]

Go to cmd prompt
Start --> Run-->cmd
In cmd prompt type
net user
It ll list all the user names

User accounts for \\ALM1WKS88

-------------------------------------------------------------------------------
ASPNET HelpAssistant akadmin
akguest
The command completed successfully.

Just chose a user name say "hpadmin" .then type
net user hpadmin *

Type a password for the user:
Retype the password to confirm:
The command completed successfully.
That's it!!