I'm working on a project where I need to use PowerPoint from C#.net. Initially, I always created one single instance. As of today, I would like to have multiple instance running. I do that like so: Type powerpointType = Type.GetTypeFromProgID("PowerPoint.Application"); object instance1 = Activator.CreateInstance(powerpointType); object instance2 = Activator.CreateInstance(powerpointType); but when I ask for the handle of both instances, by calling hwnd = (int)powerpointType.GetProperty("HWND").GetValue(instance1, null); then I get the same handle twice. My conclusion is that the application is started just once, and the TaskManager comfirms that: Only one process. How come there is only one instance of PowerPoint running, and how can I make it work?