[strangelookingmonkey]

I hope that I'm not doing something silly but I seem to get repested error-39 errors. I have ripped a DVD I own using Mac the Ripper. When I point Popcorn 2 at the folder containing the video and audio files and start the conversion everything seems to work OK. At varying times during the conversion to MPEG 4 (or H264) I get the error " Couldn't complete the last command because there was an I/O error (your disc may be copy-protected) Result code= -36"
I converting or 'exporting' the 2 hour duration file to my desktop, so I can not understand what is going wrong. I can successfully convert shorter files from the same DVD (some of the bonus extras which are shorter in duration at approx 3 minutes)
I have disabled the power saving features of my Intel Mac.

Any ideas?