[BetterRed]

@Old-T -in post #3 Kovid Goyal, the creator of calibre, posted the following

Originally Posted by kovidgoyal

Dont put your calibre library on a networked or otherwise broken filesystem. https://manual.calibre-ebook.com/faq...rked-drive-nas

In the FAQ he referenced, there is this:

If you must share the actual library, use a file syncing tool like DropBox or rsync instead of a networked drive. If you are using a file-syncing tool it is essential that you make sure that both calibre and the file syncing tool do not try to access the calibre library at the same time. In other words, do not run the file syncing tool and calibre at the same time.

BR