Perform the following:
Click the "Change Password" button
Enter you old password and new password twice and click OK
To change your password from the command line use the net user command, e.g.
net user <username> <password> (/domain)
To change from a program use the NetUserChangePassword() call.
If the above options do not provide enough security for you, download Access manager for Windows.
Access manager provides much more security than standard ways in Windows.
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