I am not able launch JNLP applications using “Java Web Start”?

Question

Up until recently, I was able to launch/open JNLP files in Firefox using Java web start.

Don\'t know what happened all of a sudden JNL

Answer 1

I believe this is a security problem. If I download the jnpl file and execute it after a clean java 8 installation via javaws myfile.jnpl everything is working fine (I get multiple windows where I have to confirm some security problems).

Answer 2

Try Java Web Launcher, rather than Java Web Start Launcher. It worked for me.

Answer 3

If javacpl does not open and gives you Could not find the main class:, it could be that Java is confused because of changes in deployment.properties (can be found in C:\Users\<username>\AppData\LocalLow\Sun\Java\Deployment on Win7). Delete that file and everything's fine.

This bug seems to be 6 years old, cf. An app should be able to ignore properties that have become obsolete over time, shouldn't it?

Answer 4

i had the same problem here. go to your Java Control Panel and Settings... Uncheck 'Keep temporary files on my computer'. Apply changes and try again your .jnlp

Note: Tested on different machines; Windows Server 2012, Windows Server 2008 and Windows 7 64bit. Java Version: 1.7++ since my jnlp app is built on 1.7

Please let me know your feedback too. :D

Answer 5

Java web start should be enabled.
Check if javaws (Java web start is enabled for your system), Use below command in console to open java control panel.

javaws -viewer

Answer 6

In my case, Netbeans automatically creates a .jnlp file that doesn't work and my problem was due to an accidental overwriting of the launch.jnlp file on the server (by the inadequate and incorrect version from Netbeans). This caused a mismatch between the local .jnlp file and the remote .jnlp file, resulting in Java Web Start just quitting after "Verifying application."

So no one else has to waste an hour finding a bug that should be communicated adequately (but isn't) by Java WS.