First it is not caused by trying to burn too much on a disk at a low bitrate.  I have some projects that fail even when trying to burn at the maximum or near maximum bit rate.  It is a BUG in the software, probaby due to some improperly handled exceptions or one subroutine accidentally overwriting some data improperly.  There seem to be 3 different ways in which it happens.

1.  Error happens quickly after starting to burn a project.  I fixed it by going to the advanced settings and selecting PCM encoding for the audio.  This will increase the size of the data on the disk, so the video bitrate must be reduced.  If mono were an option one might be able to reduce the size quite a bit.

2.  Error happens after a long while and all of the VOB files are created.  This can be fixed by reburning, but selecting rewrite the menus and use rather than encode.  To make sure you have all of the VOBs you should play back the last one.

3.  Error happens after a while, but the VOBs are not complete.  Examine the last vob and play it back.  Virtualdub is good for doing this and is free.  Look at the very last frame.  I found that it was blank.  Re-edit the video and remove the offending frame(s).

The log file is USELESS because it does not give any information as to why the project failed.  In all three cases the error message was identical, but the causes may have been different.  Is there any way to get information that MAGIX can look at to diagnose the reason for the failure?????

I have occasionally fixed this problem by just didling the video bitrate.  In one case decreasing it slightly fixed the problem.  Unfortunately I can not recommend this software for the casual user because of this gotcha which can only be worked around by serious didling.  I never had this problem as frequently in any of the previous versions, and 2014 ran very well with no such problem.  But since the upgrade to 2015, 2014 is now causing some problems.