When you delete a user from your eDirectory tree, the Home Directory of the user is not deleted automatically. If you forget to delete the directory, then the ownership of the directory and file will change to "N/A".
After a while, if you forget this several times, there will be a number of directories that don't have owners. Most of us would would like to delete these directories, but how do we find them?
You can use an NDIR command to find the Home Directories for deleted users. For example:
NDIR * /do /owner="N/A"
This will list all the directories that have no owner.