AdUsers.AdUserProvider.GetUsers C# (CSharp) Метод

        private List<AdUser> GetUsers()
        {
            string filter = string.Format("(&(ObjectClass={0}))", "user");
            // filter = "(&(instanceType=4))";

            //   string[] properties = new string[] { "fullname" };

            DirectoryEntry adRoot = new DirectoryEntry("LDAP://" + DOMAIN, null, null, AuthenticationTypes.Secure);
            DirectorySearcher searcher = new DirectorySearcher(adRoot);
            searcher.SearchScope = SearchScope.Subtree;
            searcher.ReferralChasing = ReferralChasingOption.All;
            //  searcher.PropertiesToLoad.AddRange(properties);
            searcher.Filter = filter;

            SearchResultCollection result = searcher.FindAll();

            return (from SearchResult searchResult in result select GetUserFromEntry(searchResult.GetDirectoryEntry())).ToList();
        }