How Simple File Sharing Works

There's nothing magical about Simple File Sharing. This user interface hides the full set of NTFS permissions and applies a strictly defined set of permissions to selected objects.

Behind the scenes, here is what's happening:

• Default permissions When you create a new user account and log on for the first time, Windows XP creates an empty set of user profile folders and assigns Full Control permissions to the new user. In addition, Windows assigns Full Control permissions to the built-in Administrators group and the System account. Windows designates the logged-on user as the Creator Owner of these folders; the owner has full rights to work with the files and folders and to change the access controls on these files.
• Private folders Selecting the Make This Folder Private option removes the Administrators group from the list of permitted users, leaving only the user's account and the builtin System account on the Permissions list. (A member of the Administrators group can regain access only by taking ownership of the folder, a drastic action that is recorded in the computer's event logs and is immediately obvious to the previous owner.)
• Shared folders As the name implies, the Shared Documents folder and its subfolders are available for use by anyone with an account on the computer. Members of the Administrators group have Full Control permissions over this folder and all its subfolders. Members of the built-in Power Users group (available only in Windows XP Professional) have all rights except the ability to change permissions or take ownership of files in this folder. Finally, those with limited accounts (members of the built-in Users group) can read and open files in the Shared Documents folder but cannot create new files, modify existing files, or copy or move files to this location.