Error when using Launch

[dclark15773]

When is try to use Launch on the site http://www.routeconverter.de/webstart/en I get the following error:

You have chosen to open:

which is: application/x-java-jnlp-file
from: http://www.routeconverter.de

What should Firefox do with this file?

I have installed v7 of Java. Is there something else I need to do?

[routeconverter]

You need to have Java 6, 7 or 8 installed and the Java Plugin installed in your Firefox and activated for downloads with mime type application/x-java-jnlp-file

If that is the case a splash screen show open while downloading RouteConverter and no file download dialog.