I am having a similar issue on a Dell XPS 13 9350. I tried to follow your instructions, but the 12C HID file just reappears when I restart and still has a yellow warning flag on it. So I started Dell Support Assist and followed your instructions but it only tested my mouse and my mouse passed. It did not check my touchpad as far as I could see and the 12C HID file still has a yellow warning flag on it. I uninstalled again and restarted for good measure, but no change. I am running out of ideas about how to solve this. Can you help?