Transparent SMFL screen

Question

I just installed SFML, I did everything correctly as it seems, because the program does not indicate errors and I repeated the process carefully 3 times in codeblock and twice in visual studio (2017). I can compile the program that is used as an example on the site:

#include <SFML/Graphics.hpp>

int main()
{
    sf::RenderWindow window(sf::VideoMode(200, 200), "SFML works!");
    sf::CircleShape shape(100.f);
    shape.setFillColor(sf::Color::Green);

    while (window.isOpen())
    {
        sf::Event event;
        while (window.pollEvent(event))
        {
            if (event.type == sf::Event::Closed)
                window.close();
        }

        window.clear();
        window.draw(shape);
        window.display();
    }

    return 0;
}

This program should show a green circle, however it is opening a window of the transparent

Does anyone know the cause of this and how to fix it? If you can help, thank you.