I've recently used makemkv to move my entire DVD collection onto my new Synology DS918+ for use in serving via Plex over the network to the various TVs in my house. I had a little over 300 titles to copy, so I feel like it wasn't too bad that I only had 4 or 5 that gave me issues. Initially, I would set a problematic one aside and move on. When I was done with the collection, I went back to the problem pile and ended up having to simply try most of them over and over until they worked. I don't know what was going on but if I simply tried again 3 or 4 times to rip with makemkv, it would finally work. My process is to insert the disc, deselect all of the check boxes and reselect the largest one. I would expand that item and unselect any of the foreign language subtitles and then hit go. This worked for the entire collection. But Back to the Future III (which is part of the trilogy box set) just won't work no matter how many times I try. The first two worked fine on the first attempt. I've pasted the process below. I've used a portable Dell DVD drive hooked up to a Macbook Air as well as the built in drive on an iMac. Same issue on both systems. Can anyone offer any advice? Thanks.
Using direct disc access mode
Cells 22-end were skipped due to cell commands (structure protection?)
Title #1 was added (18 cell(s), 1:43:13)
Title #1/0/1 was added (1 cell(s), 0:00:01)
Cells 2-end were skipped due to cell commands (structure protection?)
Title #2 was added (1 cell(s), 0:07:30)
Title #2/0/1 was added (1 cell(s), 0:00:01)
Cells 2-end were skipped due to cell commands (structure protection?)
Title #3 was added (1 cell(s), 0:16:18)
Title #3/0/1 was added (1 cell(s), 0:00:01)
Cells 2-end were skipped due to cell commands (structure protection?)
Title #4 was added (1 cell(s), 0:01:35)
Title #4/0/1 was added (1 cell(s), 0:00:01)
Cells 2-end were skipped due to cell commands (structure protection?)
Title #5 was added (1 cell(s), 0:01:07)
Title #5/0/1 was added (1 cell(s), 0:00:01)
Cells 2-end were skipped due to cell commands (structure protection?)
Title #6 was added (1 cell(s), 0:01:17)
Title #6/0/1 was added (1 cell(s), 0:00:01)
Cells 2-end were skipped due to cell commands (structure protection?)
Title #7 was added (1 cell(s), 0:20:39)
Title #7/0/1 was added (1 cell(s), 0:00:01)
Cells 2-end were skipped due to cell commands (structure protection?)
Title #8 was added (1 cell(s), 0:02:17)
Title #8/0/1 was added (1 cell(s), 0:00:01)
Cells 2-end were skipped due to cell commands (structure protection?)
Title #9 was added (1 cell(s), 0:01:13)
Title #9/0/1 was added (1 cell(s), 0:00:01)
Cells 2-end were skipped due to cell commands (structure protection?)
Title #10 was added (1 cell(s), 0:04:07)
Title #10/0/1 was added (1 cell(s), 0:00:01)
Cells 2-end were skipped due to cell commands (structure protection?)
Title #11 was added (1 cell(s), 0:00:47)
Title #11/0/1 was added (1 cell(s), 0:00:01)
Cells 2-end were skipped due to cell commands (structure protection?)
Title #12 was added (1 cell(s), 0:00:58)
Title #12/0/1 was added (1 cell(s), 0:00:01)
Cells 2-end were skipped due to cell commands (structure protection?)
Title #20 was added (1 cell(s), 0:00:24)
Title #20/0/1 was added (1 cell(s), 0:00:01)
Cells 2-end were skipped due to cell commands (structure protection?)
Title #21 was added (1 cell(s), 0:00:06)
Title #21/0/1 was added (1 cell(s), 0:00:01)
Cells 2-end were skipped due to cell commands (structure protection?)
Title #22 was added (1 cell(s), 0:00:13)
Title #22/0/1 was added (1 cell(s), 0:00:01)
Cells 2-end were skipped due to cell commands (structure protection?)
Title #23 was added (1 cell(s), 0:00:08)
Title #23/0/1 was added (1 cell(s), 0:00:01)
Title 2 in VTS 2 is equal to title 1 and was skipped
Title 3 in VTS 2 is equal to title 1 and was skipped
Title 4 in VTS 2 is equal to title 1 and was skipped
Title 5 in VTS 2 is equal to title 1 and was skipped
Title 6 in VTS 2 is equal to title 1 and was skipped
Title 7 in VTS 2 is equal to title 1 and was skipped
Title 2 in VTS 4 is equal to title 1 and was skipped
Title 3 in VTS 4 is equal to title 1 and was skipped
Title 2 in VTS 9 is equal to title 1 and was skipped
Audio stream #0 looks empty and was skipped
Audio stream #1 looks empty and was skipped
Audio stream #2 looks empty and was skipped
Audio stream #3 looks empty and was skipped
Audio stream #0 looks empty and was skipped
Audio stream #0 looks empty and was skipped
Audio stream #1 looks empty and was skipped
Audio stream #0 looks empty and was skipped
Audio stream #0 looks empty and was skipped
Audio stream #0 looks empty and was skipped
Operation successfully completed
Saving 1 titles into directory /Users/•••••••••••/Movies/BACK_TO_THE_FUTURE_III
Failed to save title 0 to file /Users/•••••••••••/Movies/BACK_TO_THE_FUTURE_III/title_t00.mkv
0 titles saved, 1 failed