I have a USB 2.0 hard drive that I have been using to back up movie files. It has let me transfer files from my Macbook Pro HD to it hundreds of times without any problems. I have this .mkv file that keeps giving me an error when I try to transfer it to my external. I get "Sorry, the operation could not be completed because an unexpected error occurred. (Error code 0)". I have transferred plenty of .mkv files to my external with no problems. All other files work fine when I transfer them. It will let me move my .mkv file around my Macbook Pro's internal hard drive but it won't let me transfer it to the external. Any ideas?