Maybe someone knows why

[MTUSUPPORT]

The Answer is located at: http://forum.mtu.com/showthread.php?p=23759#post23759

Here is what the problem is:

5) Error: 'TEST UNIT READY' command failed on device 1:1:0. Device contains no disc or is not ready. (04h 00h 02h 02h 3Ah 00h or Error: 'Start DAO Recording' command failed on device 3:0:0 Disc type is not supported.

NOTE: This only occurs with the Plextor PX-W708 or PX-W712 DVD Recorder Models.

Solution: Remove Roxio EZ CD Creator 6 and Nero 6. These software programs cause the error.