Zenith ZRY-316 Video Recorder "dvd show unknown disc" Questions

...and won't format it. I have tried several different brands od DVDs, but none have worked. machine might only take - dvd or + dvd only some take both types will show on front of machine just a ...

...least all other normal devices. So with this workaround devices with an LG DVD Recorder in it, which sooner or later will show the Disc not Recognized problem, are still usable as a recording