"Failure to add book" err on new setup... works fine elsewhere

[WhoMe_YesYou]

Recently updated my PC (Win10) and shifted my libraray across to be hosted on my NAS.

Had some previous books loaded into Calibre just to test the install worked but hadn't the time to shift them ALL across until now... (note: files are on NAS, just not imported into Calibre)

First attempt unsucessful... "Failure to add book"

Updated to Calibre 5.6... another unsuccessful attmpt and same error.
Read err text, not making sense to me.

Fire up laptop (running Calibre 5.5) import same file from NAS into Calibre and everything's OK.

Back to PC, try again and same err. Now i'm onto the help to see if smarter people can help me discern what's going on...

Here's the Err Info. Any help would be greatly appreciated.

----------------------------------------------------------------------
Failed to add the book: untitled
V:\Library\_Import\Drawing for Product Designers.pdf
With error:
Traceback (most recent call last):
File "calibre\gui2\add.py", line 423, in add_book
File "calibre\db\legacy.py", line 334, in create_book_entry
File "calibre\db\cache.py", line 72, in call_func_with_lock
File "calibre\db\cache.py", line 1654, in create_book_entry
File "calibre\db\cache.py", line 1367, in set_metadata
File "calibre\db\cache.py", line 1191, in update_path
File "calibre\db\backend.py", line 1645, in update_path
File "calibre\db\tables.py", line 134, in set_path
File "calibre\db\backend.py", line 920, in execute
apsw.CantOpenError: CantOpenError: unable to open database file

[ownedbycats]

Originally Posted by WhoMe_YesYou

Recently updated my PC (Win10) and shifted my libraray across to be hosted on my NAS.

Take your library off your NAS and try again.