For every successful registration, Roku sends an activation code which is required to link your Roku with your Account. Roku Activation code are also required in activating every channel. You cannot buy channels directly from your ROKU device but you will require activating each channel via Roku Activation Code. If you want any help related to activation code call us at USA/CA: +1-888-271-7267 and UK/London: +44-800-041-8324