The database on the device is fine. I have all my reading stats, all my current reading locations. Everything is fine on the device.
When I use the plugin to fix errors on the device database it simply shows
When the "automatic" backup happens when I plug in the device (if I have it so configured) happens, it throws an error. BUT, when there is no automatic backup, or when I manually use the plugin to create a backup, the backup completes with no error.
Again, as noted in my troubleshooting, if I change the target location of the backup from a remote disk on my LAN to a local hard disk, the problem vanishes. But when I set it back to the remote disk again, the problem reappears.
I wouldn't say the problem is with the remote disk, per-se, since manual backups complete without error, and Calibre is storing its database and ePub files there. But something is off with regards to the automatic backup on a remote disk.