could not be copied because an error occurred. The required file cannot be found
when i copy folder to itunes app, pop up this error, for this error, i figure out the reason, it looks like itunes has limitation for folder and file name.
- there must be no () in folder name
- the file name longth is limited, i don't know the exactly limited number of file name characters, but i modify the long name to short one, it works.