There are some security features automatically built into this logbook software by virtue of the Java WebStart deployment method, and other features employed in the development of this application.
When you start the application you will see the "Welcome" splash screen followed by a login dialog box; if it has been enabled in configuration. The first time the application launches, with this featured enabled it will say you are a new user, it will ask to "please enter your username and password". If you simply hit the login button, the logbook will launch without needing username and password. If you plan on being more secretive about your log time, and want to keep it from your spouse, kids or the FAA Investigators(this is a joke). Then enter a username and password. Then everytime you launch the application it will ask you for a password. The login feature can be disabled or enabled through the configuration menu under tools.
The password can be changed anytime. This is done after you are in the application, click on Tools -> Update Password, or if you like short cuts press CTRL-U. The login dialog box appears but asks for the old password and new password. If there is a problem with the old password it won't update the account to the new password. This part of the verification process it only allows updates to the new password after verification of the old password.