Video Playback / Recording Devices

i am having trouble burning dvds, i have dual drives, i am using a liteon smh 165h6s040. it had been doing great. i have two burning programs, nero, and 1 click copy dvd. It started last week it would burn disc, and said burn was sucessful, but when i tried to play disc, they would not load,or eject from dvd player. finally this week it won't burn but about 30 percent, using nero to burn or 1 click copy. it tells me read error and write error. i reinstalled programs but it did no good. i changed  source and destination drive to use just one drive, and it does the same thing.

can any one please help i have just been given a sony rdr-vx420 dvd / video recorder and i am trying to set it up (with the instructions ) i need to connect the recorder to a tv and a digi box , i have been on sonys website and printed off the diagram for this set up but when i set up as instruction book and the sony diagram the set up will not let me do anything with the digi box ie change channels and im not sure where the incoming signal is going as the picture quality is not the same as when i use the digi box on its own with the tv you may be confused but believe me i am !!!

My Magnavox DVD/VCR player/recorder has started displaying an error message as follows:

    Error Can not record on this disc.

     E4  54037380

It displays this message no matter what type of disc is in the machine.

Does anyone have any insight on this issue?