Update May 13, 2014:
IDS has released a tool for Windows which automates the process of associating JNLP files with Java.
Click here to download the JNLP Fix tool. When the program has finished downloading, click run or double-click the “jnlp-fix” program icon to start the process. The “jnlp-fix” program can be deleted once the process is complete.
If you run the program and JNLP files still do not open with Java, please follow the steps below to fix the problem manually.
Is your computer having difficulties associating the join.jnlp file to Java? When a session is opened, the join.jnlp file should try to open using Java. You should get a prompt that looks like the following:
If the Java file isn’t being recognized, you may have to manually associate the “.jnlp” file to Java. Next to the “Open With” option, it should read “Java(TM) Web Start Launcher (default)”. If you get a screen that does not have this option, that would indicate that Java is not properly associated with the .jnlp file type that’s needed to launch Collaborate.
When Java is normally working, you would “Open” the file. But we need to save the file this time in order to get to the properties panel for that file type. Select “Save File”, then click “OK”, and save the .jnlp file to your desktop.
Find the join.jnlp file on your desktop that you just downloaded, Right-click on the file and select “Properties”.
Under the “General” tab, next to “Opens With”, click the “Change” button.
Browse to locate the file : “javaws.exe” Usually the Java web start launcher is located in: C:\Program Files\Java\jre7\bin – (jre7 if you have Java 7, jre6 if you have Java 6).
It should look like this: (Click “OK” on the “Open With” screen below once you have “Java Webstart Launcher selected.)
Then “OK” again on the “Join Properties” window.
Java should be associated with the Webstart Launcher now.