Tried to search for an answer for this problem, but could not find one.
After I have transferred my book from Calibre to the SD Card on my Nook Color, I can see that Caliber shows that the book is on Card A. Once I eject my Nook and try to view the book, it is gone from the SD Card. The directory is there on my SD Card, but no files in the directory. I have tried this several times.
If I transfer the book to my main memory, I don't have any problem.