Nvidia 3D vision not working in Prepar3D windowed mode (help)

In FSX I can use Nvidia 3D vision in fullscreen and in Windowed mode.

Today I installed P3D 1.4 and can only use 3D in fullscreen mode.

I can remember that I was using FSX and P3D 1.2 beside each other and P3D was working ok in windowed screen mode.

I need to fly in windowed mode because of the FSInn/FSCopilot screen in the upper corner while flying online with Vatsim.

When using it in fullscreen mode my 3D mode fall back to standard 2D

Please don't make the mistake with 2D cockpit and 3D virtual cockpit, that is not the issue.

I am flying normally in stereo 3D with Nvidia 3D Vision and 3D shutterglass.

Happy landings...