You are right, I forgot to give more details...
And the log :
Code:
calibre, version 2.22.0
ERROR: Error: Error communicating with device
database disk image is malformed
Traceback (most recent call last):
File "site-packages\calibre\gui2\device.py", line 87, in run
File "site-packages\calibre\gui2\device.py", line 503, in _books
File "site-packages\calibre\devices\kobo\driver.py", line 1787, in books
File "site-packages\calibre\devices\kobo\driver.py", line 1663, in get_bookshelvesforbook
DatabaseError: database disk image is malformed
I read your suggestion, about logout and in to get back a fresh database, it works but as soon as i reuse Calibre, my database corrupts.
Thanks for your help, davidfor...
EDIT :
I know now how to starts with a clean database thanks to tshering, but it corrupts as soon as Calibre needs it : either by refreshing the field about shelves, or by adding a book (even only one).