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I have a Java Web Start application I launch with a JNLP file successfully without the corporate firewall, but I can't get around this problem: Unable to load resource: url://file.jnlp

When I use my Mac OS X Terminal to launch it, I see:

PROMPT$ javaws -Xnosplash file.jnlp

java.lang.IllegalArgumentException: port out of range:-1
... rest of stacktrace ... 

I am aware that Java Web Start tries to open a server listening on a random port for the splash screen, which is why I try adding -Xnosplash to the command.

I know that the app only uses port 80 other than the splash screen.

How can I get the app running by myself or what do I ask my IT dept. to open up so I can do so?

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up vote 2 down vote accepted

FailedDownloadException is thrown from the class, and means that for some reason your local configuration does not allow loading of Java Web Start startup file. This can be because there is a strict proxy on your local network or because your local security package is configured to block JNLP files. It can also mean an error in the application or a bug in the Java runtime.

Some ideas:

  1. Check the version of the Java runtime. Later version is not always better.
  2. Turn off all security software on the computer and in the browser
  3. If there is a proxy involved, check its parameters
  4. Turn off IPV6
  5. Verify that the JAR's URL is well specified in the JNLP
  6. Verify that the JAR is well signed and that its Certificate Authority (CA) is recognized on the computer
  7. Are you sure that there is no firewall between the Mac and the server?
share|improve this answer
I'll give these a shot and let you know. I'm guessing there is a firewall, though. I was hoping I could prevent Java Web Start from doing anything on non-standard ports (like the splash screen). Is that possible? – Eric Wendelin Jul 22 '10 at 12:49

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