Recently started getting the message "the itunes library file cannot be saved. an unknown error occurred (-50)". When iTunes is closed and reopened the message "The itunes application cannot be opened. An unknown error occurred (13014)" appears. Reinstall iTunes and restart and maybe get a couple days before it occurs again. Or, 5 minutes like just happened. ***Disregard for now. My iTunes library is on the Optibay internal data drive in a MBP. I think that checking "Ignore ownership on this volume" may be the fix. The Lightroom catalog (also stored on the 2nd internal drive) would not open the past two days, but will now. If anyone knows why these issues have cropped up just recently regarding accessing data on the 2nd internal drive, that would be helpful.