The key is where you compile your new project to. It needs to be another name, of course, and another virtual directory. I'm assuming you created it with the WebAppBuilder. You should be working in the yourproject project. My advice is to always use the projects, not just main.prg outside of your project. This is the project that WebAppBuilder created. When you make a change, though, you should only have to compile the main.prg in your project.
>hi cloude,
>
>i thing there are two main prg files in my hd, one is that coping/install when your software install on my computer and scond is when i create any project . Both are diffirent paths, when i change the hello word from main prg file,(this prg found where i have installed the programm)hello word changed, But when i changed the hello
>work from my project i have not any change.