I have installed windows vista and Nero.Ultra.Edition.Enhanced.v126.96.36.199. When I want to burn cds everything goes alright. However when I want to burn dvds everytime it reaches only 1% and then shows PMA Update failure and could not perform Disc-at-once. So,the burn is cancelled and the dvd is lost... I have an LG DVDR. Also when I burn the dvd automatically when I create a movie with ConvertXtoDvd everything goes OK. Does anyone know what it has to do with? Is it a software or a hardware problem. Thanks a lot.