"Using OS scope before setting MAKEFILE_GENERATOR" in Qt
===

I have downloaded and installed Qt and I'm learning how to use it.
So, I created a new project `myfristqt` (empty project). I then added a `main.cpp` file with this code:

    #include <QApplication>
    
    int main(int argc, char *argv[])
    {
        QApplication app(argc, argv);
        return app.exec();
    }

First thing I noticed `#include <QApplication>` line is hightlighted with a red line as if `QApplication` was an unknown identifier. So, I compiled it to see what happens and here's the error I got:

    (internal):1: error : Using OS scope before setting MAKEFILE_GENERATOR

Any idea why this is happening ? I'm using Windows XP








 