Re: problems using two controllers on XBox One

On the second controller, does the light ever remain solid?

Generally if the light is blinking it means the controller is trying to connect to a console. To connect a controller to the console, press the Sync button on both your controller (top of the controller, between the bumpers to the left of the cord plug in) and the console (silver button on the side, near the side USB slot). Once the controller is synced to the console, the button will remain solid and no longer blink.