Were preparing to migrate our Windows 2003 file server to a new share on an Isilon NAS (which supposedly supports NTFS permissions). Ive performed a few test runs using Robocopy with the following syntax: Robocopy <source> <destination> /MIR /SEC it appears that all of the NTFS ACLs migrate properly, BUT there appears to be a discrepancy on how it interprets the permissions compared to the way the current Windows 2003 server interprets them. Heres the quandary: We have a folder, lets call it Private on our current Windows 2003 system that all of our users, lets call them the Users_Group should be able to access. This Private folder also houses tons of other subfolders, however members of the Users_Group should not be able to see all of the subfolders within the Private folder, just the ones they explicitly have permission to. After the robocopy was completed, we opened up the Private folder on the Isilon NAS and ALL of the subfolders were listed. Granted, users cannot access the ones they arent explicitly granted access to, however ALL of the folders are in plain sight. I cross referenced ACLs, inheritance, the whole 9 and cant seem to figure out how to disable listing ALL of the folders, instead listing only the folders a specific user has been granted access to. Any help would be greatly appreciated.

Ah... it's called Access Based Enumeration. "Makes visible only those files or folders that the user has the rights to access. When Access-based Enumeration is enabled, Windows will not display files or folders that the user does not have rights to access." Not sure if the Isilon NAS supports this, but will do some more digging.