Why can't I run Java Web Start Applications?

I have Ubuntu 12.10 for x86-64 on my PC and I'm trying to run a .jnlp file. I've installed Java 7 and the Java plugin for Mozilla Firefox manually (because there is no .deb package for Java 7 for Ubuntu).

Whenever I double click a .jnlp file, Firefox is opened and it gives me the option of opening the file with Firefox or saving it. If I click save, it download the file I'm trying to run, and if I click open with Firefox web browser, it opens another tab and asks me again (in the new tab) to either open or save.

I used to run the exact same file on Debian, so what should I do to run this file on Ubuntu?

First install the icedtea-8-plugin package (or later version) that include the java browser-plugin and the javaws webstart tool that can launch .jnlp files.

Use javaws to open the downloaded .jnlp file.

Have you tried verifying that java is working properly? You can use this link to see if it is. http://www.java.com/en/download/installed.jsp?detect=jre If not, You'll have to get it enabled properly. I'm still a bit of a Noob but I had that same problem. Regards

For Ubuntu 19.10, use:

sudo apt install icedtea-netx