Oculus DK2 reacts to OpenDS but my Oculus screen stays black

Hey everyone,
for my thesis I programed a driving simulator with OpenDS and I want to test it with my Oculus (the program is compatible with DK2).
When I start my scene I can see the Oculus view on my monitor and it reacts to the movements of the oculus but whether on the oculus nor on the sensor lights the LED and the oculus screen is black.
I tried everything I could find on the internet and installed and deinstalled everything a few times but nothing changed.
Does anyone has another idea?

Thanks a lot for your help!