Security permissions are changed when you copy or move files or folders. Summary:
When a file or a folder is created, it inherits permissions from the parent folder.
When a file or a folder is copied to another folder on the same or a different partition, it inherits the NTFS permissions of the destination folder.
When a file or a folder is moved to another folder on the same partition, its NTFS permissions are maintained ASIS.
When a file or a folder is moved to another folder on a different partition, it inherits the NTFS permissions of the destination folder.
When a file or a folder is copied or moved to a FAT partition, all permissions are lost since FAT partitions do not support permissions.
When a file or a folder is copied from a FAT partition, it inherits permissions from the destination folder.
These rules are very straightforward and easy to remember, especially once you realize that moving a file to another partition actually copies the file to the partition (and so the file inherits the permissions of the destination folder) and then deletes the source file.
When applying permissions to a folder, you have two additional options:
The Replace Permissions On Subdirectories check box will propagate all the permissions on the current folder to all its subfolders.
The Replace Permissions On Existing Files check box will propagate the permissions set on the current folder to all the files in it.
