When I Run Main Project in NetBeans (F6) It always runs a project that isn't even open

I'm new to using NetBeans and Java but am learning lots from the book Head First Java which I love.

However, I am having a problem with NetBeans when I click on the green arrow(Run Main Project F6) button. It keeps trying to run my project and then looks for a class in another completely unrelated project, which isn't even open. I don't understand how that can be happening. This class is not even in my code yet it is trying to compile with it. I have attached a screen print.

I am running the BeatBox application from the book and it keeps looking for the QuizCardBuilder class, which is in another project. This happens even if I open ANY other unrelated projects and try to run them. They all keep asking for the QuizcardBuilder class. It's crazy.

Can you try right clicking on the project you want to execute and click Run, rather than using run main project. I suspect its always running the project that has been set as main project when you hit F6

If at all possible, don't use IDEs until you are a lot more experienced. You quote the name of the class with your main method at the command line/terminal

javac MyClass.java
java MyClass

Note when you do and don't use extensions.

I'm going to take your advice and stop using the IDE for now. I just started using it for the last few projects because it looked like it made things easier but it's caused more confusion.

I wasn't having any problems when I was running things from the DOS prompt.

Thanks again.