[PeterT]

Actually yesterday on one sync I saw the infamous

Spoiler:

*** in database main ***
Main freelist: 1 of 3133 pages missing from overflow list starting at 22592
Page 20997 is never used
wrong # of entries in index shelfcontent_datemodified_index
wrong # of entries in index sqlite_autoindex_ShelfContent_1

Traceback (most recent call last):
  File "site-packages\calibre\gui2\device.py", line 87, in run
  File "calibre_plugins.koboutilities.jobs", line 186, in do_device_database_backup
Exception: 
*** in database main ***
Main freelist: 1 of 3133 pages missing from overflow list starting at 22592
Page 20997 is never used
wrong # of entries in index shelfcontent_datemodified_index
wrong # of entries in index sqlite_autoindex_ShelfContent_1

I said Oh HECK then realized I still had Kobo Dekstop running in addition to calibre.

Shut down Desktop, ejected and re-attached Kobo; no errors.

Would be their be any benefit to checking in either Kobo Driver or Kobo Utility for the presence of Desktop, and alerting the user?