I have the PHANTOM 2 with the ZENMUSE H3-HD.
Been trying to connect the downloaded gimbal software on my PC to my Controller, but for some reason it does not recognize the Controller.  I am unable to calibrate my Controller so it can control the gimbal.  Am I missing something here?  (DJI WIN Driver installed)
When I launch the app with the Controller connected via USB, neither of the 2 LEDs come on.

Any help would be greatly appreciated.  

You are using the P2 Assistant for the airframe and the Gimbal Assistant for the H3-3D?
If the Gimbal Assistant is not seeing the connection to the H3-3D, it could just be a finicky USB connector or cable.
Lots of times I'm either too fast or too slow plugging the USB cable in to DJI devices, and nothing happens.
I'd try the present cable a few more times, and then perhaps try another cable...

You must use the p2 assistant to update the gimbal.. The h3-3d assistant is for the stand alone version.

Blade_Strike Posted at 2014-9-30 00:21
You must use the p2 assistant to update the gimbal.. The h3-3d assistant is for the stand alone vers ...

Definitely try another usb cable.  Some cables do not use all the pins which is probably what is causing the problem.  I had the same issue.