how to add shared folder(ext HD) in appleTVflash(black).. MAC OS

Hi! Just got an iMAC… I connect the usb external hard drive with my mkv movies, make it shared folder in “system preferences” menu, but cannot “see” it in “manage shares>add share option” in apple tv [appleTV flash(black) 4.0]. The “public folder.drop box” folder is located by the apple tv though,and when i copy a movie in it i can be reproduced  just fine! Moreover the “PLEX” player can stream movies fluently via “plex media player” installed in the iMAC! 


Just a few obvious things to check:

Under system preferences on your iMac in the sharing tab:

  1.  Is you external drive listed under the ‘Shared Folders’ column

  2.  Is the file sharing on tick-box enabled

  3.  Under ‘Options…’ have you ticked ‘Share files and folders using AFP’

Also, how is your external drive formatted?  I don’t think this sharing works with NTFS formatted drives; you must use FAT32 or MacOS format.  When I had this problem it was because when I moved from PC to iMac my ext drive was still NTFS.  As far as I was aware, media player uses AFP and AFP does not work with certain drive formats. (I only ever got this working reliably when I formatted my external drive as MacOS)