* The error number 003 denotes a software upgrade failure. You must first change the connection type before attempting to update in order to resolve this problem. * You will be able to install the update without any issues if you connect the Roku to your network via Ethernet connection. * Get an Ethernet cable and connect it to the Ethernet port on the router and the Ethernet port on the Roku device. * Select the proper input channel on your television. Turn on the Roku device and use the remote to scroll through the available selections. * If these suggestions fail to resolve Roku Error Code 003, contact the technical support staff. Read Also: How to fix roku hdcp error | How to fix Roku Error Code 005