Also, from the content of your log-file, I've got the impression that there isn't a single well-formed backup chain in your backup directory. Can you check with:
ls -l /home/david/Dropbox/Backups
Also, from the content of your log-file, I've got the impression that there isn't a single well-formed backup chain in your backup directory. Can you check with:
ls -l /home/david/ Dropbox/ Backups