One more question about using a NAS/fileserver

[Labernase]

One more question about using a NAS/fileserver:
I’ve learned that a fileserver/filesystem is a “complex beast” ...

Well, in the first case – 3 Macs and a NAS from Apple – it seems to be able to store the library on the NAS so that all users have an access to it.

In the second case I would create a library on a Windows-Sever to have access from 3..5 Windows-PCs (never at the same time – we know that rule). First I created a new library with a path to a directory on the server. This directory has our “crew” as owner (with full access) and all users are member of the “crew”.
If I put a document into the library everything seems to be ok. There is a new directory at “\\server\ …\Vogel” (a new author) and a subdirectory with the title as name (“Technology”).
But if I want to change anything (e.g. author or title, here: "Vogel" into "Alfred Vogel") I get an error message:

calibre, version 3.10.0
FEHLER: Access denied: Der Speicherort dieses Buches konnte nicht verändert werden. Ist es noch in einem anderen Programm geöffnet?

Locked file: \\server\...\Alfred Vogel\Technology (7)\cover.jpg

Traceback (most recent call last):
File "site-packages\calibre\gui2\library\models.py", line 1091, in setData
File "site-packages\calibre\gui2\library\models.py", line 1166, in _set_data
File "site-packages\calibre\db\legacy.py", line 441, in set
File "site-packages\calibre\db\cache.py", line 62, in call_func_with_lock
File "site-packages\calibre\db\cache.py", line 1095, in set_field
File "site-packages\calibre\db\cache.py", line 1109, in update_path
File "site-packages\calibre\db\backend.py", line 1561, in update_path
File "site-packages\calibre\db\backend.py", line 1347, in copy_cover_to
File "site-packages\calibre\utils\filenames.py", line 429, in copy_path_to
File "site-packages\calibre\startup.py", line 116, in local_open
IOError: [Errno 13] Permission denied: u'\\\\server\\...\\Alfred Vogel\\Technology (7)\\cover.jpg'

At the same time there is a new directory named “Alfred Vogel” and a subdirectory “Technology”. In this subdirectory one can find the file “cover.jpg” but no pdf.

Last but not least – calibre has changed in the library the author to “Alfred Vogel” but the path-link wasn’t change – it is already “\\server\ …\Vogel”

What can I do to allow changes in library books?

Many thanks!