I'm hoping to use QT Creator as a C IDE on a Windows box - I assume there's nothing wrong with using it like this, right?

I've downloaded the QT Creator binary for Windows (40 Mb), and installed this. I'd hoped the inbuilt MingW toolchain would just work out of the box, and I could just it right away.

However, when I create an empty C or C++ file, I can't seem to compile it. The first include line:

#include <iostream>
is flagged with the error:

iostream: No such file or directory
Same happens with stdio.h, of course.

Also, all of the options under the Build menu are grayed out.

Is there something special I need to do, to get QT Creator to work under Windows, and compile C or C++ programs?