SHARP DVD/VCR COMBI DV-RW360 WILL NOT RECORD ON TO DVD-RW?

SHARP DVD/VCR COMBI ,DV-RW360H THE RECORDER FOR SOME REASON WILL NOT RECORD ON TO ANY MAKE DVD-RW, COMES UP ERROR E4 54040990 ,IT SEEMS TO FINALISE THE DISC MAKING IT USLESS TO USE AGAIN.BUT WILL RECORD ONTO DVD-R.I HAD THOUGHT THAT PUTTING THE RECORDER BACK TO FACTORY DEFAULT WOULD SOME HOW HELP,BUT I CANNOT FIND A WAY OF DOING THIS,TO SEE IF THIS CAN HELP.PLEASE ANY ONE THAT CAN HELPME;