I was following this tutorial: 
<https://netbeans.org/kb/docs/java/native_pkg.html#tool>

and I did everything exactly as they explained to make an EXE file from a Java project (not a JavaFX project), which is the first part of the tutorial. 
(the lower part is about JavaFX)

The EXE file is created, and I can install the application (by executing the EXE file).
But when trying to run, it says: "JavaFX Launcher Error: unable to invoke main method". 

Any ideas? 

I supose its recognizing the java file as an JavaFX project file, so its looking for the method **start()**, but I have no idea how I would solve this.