Illegal disc cannot burn

i have plextor 708
using dvd decrypter, dvd2one, and nero.
firts i copy to hdd, then shrink and, then try to burn it but i keep getting illgeal disc. what gives? any help and other ways to back up would be appreciated

Have you tried using other media? What kind of disc are you trying to burn? Please identify it with DVD Identifier and report back!