If you move an item between two folders on the same NTFS volume, the permissions of the moved item would not change. Since Windows Vista and 2008 this is no longer the case. Windows Explorer changes the permissions of the moved item, so the permissions will be inherited from the target location (a move operation by something else than Windows Explorer, still retains the original permissions). A special situation arises with Windows 7 and Windows 2008 R2. In these cases, the permissions are sometimes inherited from the target location, and sometimes aren’t. Not really consistent and this could pose a big risk when using these Operating Systems in move operations on your fileserver. It is completely random what will happen to the NTFS permissions of moved files…. Or is it not…,?
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I ran into this myself and then found this article that explained exactly why this seemingly random behaviour occurs http://think-like-a-computer.com/2011/07/24/moving-files-on-the-same-ntfs-volume-does-inherit-permissions/