1)Reboot the Xbox 360 console.
2)If your console is not connected to Xbox live, your Xbox 360 will not get automatically get updated to the latest firmware. The firmware you are currently running on your Xbox 360 console can be damaged, so it always best to update the firmware on your console.
3)Make sure the power unit that connects into the hd DVD player is firmly connected into the electrical outlet and inserted into the hd DVD player correctly. As well as check the power connections, make sure you also check if the usb connector is plugged into the usb port on the console. Switch on your Xbox 360 console and switch on the power to the hd DVD drive, do you get a green light on the button? If not, then there is something wrong with the power unit, so check the fuse in the plug.
4)Plug in the usb connector, that connects the hd DVD drive to the console into a different usb port on the console.
5)Use a compress can of air to clean the usb port your using to recognize your hd DVD. Sometimes dust and dirt can prevent a good electrical connection to occur, which can prevent your console from recognizing the player.