NTFS Permissions

Як програмно дати ASPNET користувачу права на запис в папку?

DirectoryInfo di = new DirectoryInfo(path);
if (di.Exists)
{
   DirectorySecurity ds = di.GetAccessControl();
   FileSystemAccessRule fsar = new FileSystemAccessRule(
       new NTAccount(Environment.MachineName + "\\ASPNET"),
       FileSystemRights.Write | FileSystemRights.ReadAndExecute |
       FileSystemRights.Read, AccessControlType.Allow);
   ds.AddAccessRule(fsar);
   di.SetAccessControl(ds);
}