James, here are notes I added to the report. And **sigh** it appears to be just that one new archive. At least the other, which I had captured successfully afterwards, is now being captured again. (Sorry -- I get befuddled with terminology here: 'Capture' meaning in this case, capturing to a pre-existing archive, from an HD previously backed up to that archive; distinct from 'Recapture'?? Or what am I missing, still after 'x' years?
At any rate it does appear the large, new archive is the culprit.
EDIT - I attempted 'REPAIR' from the QR FILE menu. After confirming the volume OK I chose REPAIR without checking any other box. As soon as the repair began it failed - here are the log entries:
Action 2015-11-26 09:02:30 ------- Repair 1TB_FOTO_ARCHIVIO_PORTABLE_HD
Action 2015-11-26 09:02:30 archive: /Volumes/TO BACK 03 3T/1TB_FOTO_ARCHIVIO_PORTABLE_HD.quanta
Action 2015-11-26 09:02:30 Failure Failed
Action 2015-11-26 09:02:30 problem setting EOF
Action 2015-11-26 09:02:30 Failure Repair failed
Action 2015-11-26 09:02:30 A network or disk error was encountered.
Action 2015-11-26 09:02:30 ------- Repair incomplete (00:00)
But it got worse. As a double-check I tried to repair the second archive, the one I successfully updated and that seems ok. The repair started ok, and after a couple of minutes I clicked 'STOP'. After perhaps another minute a message came forth saying the archive index was damaged needed to be reindexed. This seems odd to me, but I am presently reindexing that archive, following the prompts.
Going back to the original issue of the QR quitting on trying to recapture the larger HD, here is more, my notes I included with the report I sent:
During the backup from the external HD to the new archive I trashed several large files from that HD. QR completed the capture, then went into a verify and reported problems with both the backup and the verify.
I opened the archive and eliminated the items I had trashed from the HD.
I then made a capture from a different external HD, previously archived with QR to it?s separate previous archive. That went off no problem.
After that I tried to capture the first HD again and at that point QR quits the moment I click on OPEN to start the new capture to update the archive.