In Windows 7 desktop, there is no quick launch. Instead we get a default program list in big Icons (e.g., Internet Explorer, Windows File Explorer). It’s cool feature that you can add your own mostly used programs like quick launch.
When you try to open second instance the already opened program by clicking on the icon the task bar, it opens the running instance.
Simply Middle click on the icon the taskbar (any icon), it will open a new instance of the same program. 🙂