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Firefox has no JNLP association how do I make one?

  • 4 replies
  • 18 have this problem
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  • Last reply by cor-el

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I have downloaded a JNLP file from http://phet.colorado.edu/en/simulations/category/physics for a physics class that I'm taking, but the file will not load or start in Firefox. Java Web Start has already been installed by the system administrator but there is no file association for, nor is there a "JNLP" file type listed in Firefox --> Tools --> Options --> Applications

How can this be fixed so that the "JNLP" file type is listed in Firefox --> Tools --> Options --> Applications?

If you can get me that far I can do the rest by making the file association to javaws.exe. Thanks.

I have downloaded a JNLP file from http://phet.colorado.edu/en/simulations/category/physics for a physics class that I'm taking, but the file will not load or start in Firefox. Java Web Start has already been installed by the system administrator but there is no file association for, nor is there a "JNLP" file type listed in Firefox --> Tools --> Options --> Applications How can this be fixed so that the "JNLP" file type is listed in Firefox --> Tools --> Options --> Applications? If you can get me that far I can do the rest by making the file association to javaws.exe. Thanks.

All Replies (4)

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Is the file supposed to open externally in Java Web Starter? The combination of choosing a program using the Browse button and checking the box to do that from now on should add a new preference for you. Otherwise, there isn't a straightforward way to do it (the format of records in mimeTypes.rdf doesn't seem well documented).

If the file is supposed to be handled by the Java plugin, I wonder whether the setting in the Java Control Panel (see attached) will make any difference?

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Note that these files are send as application/x-java-jnlp-file (Java Network Launched Application), so this MIME type needs to be registered to get the JavaWS (Java Web Starter) program offered as the default choice.

  • HKEY_CLASSES_ROOT\.jnlp
  • HKEY_CLASSES_ROOT\MIME\Database\Content Type
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Sorry I should have mentioned that I'm using Linux. Specifically: Kubuntu 12.04

Since this was a java problem, I thought it could be fixed within firefox.

jscher2000: When I try your suggestion I get no option to browse for a file to open it with, and the only option is IceTea Java Webstart. When I click on that I get the error message: /tmp/faraday_en.jnlp could not be opened, because an unknown error occurred. ...and this same error occurs no matter what jnlp file firefox is trying to open.

Cor-el: As I stated in this post I'm using Linux so there is no registry to edit, and as such your solution doesn't apply to my setup. There should be a configuration file someplace on Linux to do something similar but I'm not sure how or where to even begin looking or even what to search for in google to figure that out. So I'm basically stuck.

Thanks for the input. Any other Linux based solutions would be greatly appreciated.

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I'm on Linux as well and don't have a problem with the jnlp files.
I get a pop-up window (normal Firefox open with dialog) with JavaWS selected as the default application to handle this file.