It gives an error report. I'd post what the report says but it doesn't allow you to highlight so I can't c&p it.
After reinstalling Santa last time, it allowed me to burn the files I was trying to before. As for this file that I want to burn now, Bitzi says it's a good copy and I can play it fine on the computer. So I think the files are fine.
I've just found something though. As soon as Santa starts encoding the file the error message pops up. Before, I just clicked to either send the error report or to not send and the whole programme shut down. But I've just tried not clicking anything in ther error window, moved it out of the way and found that the file is still being encoded.
So I thought that maybe I'd be able to burn the file despite having the error message up. But, it's just finished encoding and as soon as the Burn Now window should have popped up, Santa crashes.