[NiLuJe]

Okay, then, yeah, Jon's original answer is accurate enough for a stock calibre setup.

You'll either want to force a Nickel library scan via NickelMenu, or disable the Kobo device plugin in calibre to downgrade to a plain USBMS setup that won't rely on Nickel's db.

I've written about the pros and cons of these approaches... somewhere (it's in this very subforum, can't quite recall where, though ;D).