Same happened to me when I tried to copy a CD the way it has always been, the best way, to no avail. I could play it in iTunes but not download.
So, I reverted to good old drag and drop. It worked. So, just drag your CD into the Playlists column of several unnecessary columns. It will copy if you drag and drop onto the Playlist music part, not into the column on the far left of iTunes Playlist but directly onto the list itself.
Same issue that started after Security Update and OS update for iPhone. Backing up via the cloud but cannot get iTunes to recognize iPhone.
Guess I have too much Apple around here, once a glitch hits Apple hits the "it's you not me" key on any response.