wef
folder doesn't exist on your computer, create it./Users/<username>/Library/Containers/com.microsoft.Word/Data/Documents/wef
/Users/<username>/Library/Containers/com.microsoft.Excel/Data/Documents/wef
/Users/<username>/Library/Containers/com.microsoft.Powerpoint/Data/Documents/wef
open .
(including the period or dot). Copy your add-in's manifest file to this folder.