Cannot ADD ebook (error mess.)

Hi and good day,

Just starting with calibre on OSX 10.11.6 with iBooks (and iPad Air 2).

Unsuccessful to ADD an ebook (which I find in OSX Library - see screendump.)

- neither .epub nor .ibooks, same error message.

Please hv a look here:

https://www.abc.se/home/m9783/ir/x/_...ibre-error.jpg


Why I want to use calibre.app?
For easier copying text for quoting.

/
with best regards,
Omar KN
Stockholm, Sweden