Java Web Start Console
Once you have downloaded your application there will be a Java Web Start Icon on the desktop. On a windows desktop there will also be a Web Start Icon for your application. Users can click on this icon and it is the same as using a browser to navigate to the Web Site and launch the application.
In order to see Java Exceptions, your user will need to click FILE --> PREFERENCES --> ADVANCED (tab) and place a check mark beside the "SHOW JAVA CONSOLE." If they don't do this they will not be able report errors in your program like nullpointerexceptions.