Similarly, when you run JAVA or JAR files, you need the help of Java Framework to open them. When we say open JAR file, we are not opening the file like an archive file, but we are executing it.

Verify Java is associated with JNLP files using the Java Control Panel window. Open it by clicking "Start," selecting "Control Panel," clicking "Programs" and clicking the "Java (32-bit)" option.

If you have the Java Runtime Environment installed, and the JAR file is executable, it should open with a double-click. Sometimes, you might see a pop-up to choose which app to run the file.