I've been grappling with trying to get Java Web Start working over the last couple of days. When I run it on a locally installed web-server (Tomcat 6.0.26) my jnlp file works perfectly. As soon as I put it on an external web-server I get "com.sun.deploy.net.FailedDownloadException: Unable to load resource:" errors. While investigating I came across http://java.sun.com/javase/technologies/desktop/javawebstart/demos.html - and I get exactly the same error when I try to run any of these examples. Could someone confirm if this page still works for them or is this a dead page? I haven't found anything that suggests that I need to open holes in firewalls to get WebStart to work.
Joined: Jan 21, 2010
After more digging, I've found that if I change Java Control Panel -> Network Settings from Use Browser Settings to Direct Connection everything starts woking. My jnlp file works and the Sun demo site works. Would anyone care to explain the difference between these settings so I can get to the root of the problem.