Error

[ajmeer]

hai friends i having error in this below programe,my task is fetch all user information from active directory ,my error is server is not operational

string principal = this.Context.User.Identity.Name;
        return principal;

string principal = GetPrincipal();
        string filter = string.Format("(&(ObjectClass={0})(sAMAccountName={1}))", "person", principal); 
        string domain = "DOMAIN"; 
        string[] properties = new string[] { "fullname" };
        DirectoryEntry adRoot = new DirectoryEntry("LDAP://"+domain, null, null, AuthenticationTypes.Secure); 
        //DirectoryEntry adRoot = new DirectoryEntry("LDAP://" + Environment.MachineName,null, null, AuthenticationTypes.Secure); 
        
        DirectorySearcher searcher = new DirectorySearcher(adRoot); 
        searcher.SearchScope = SearchScope.Subtree; searcher.ReferralChasing = ReferralChasingOption.All; 
        searcher.PropertiesToLoad.AddRange(properties); 
        searcher.Filter = filter;
        SearchResult result = searcher.FindOne();
        DirectoryEntry directoryEntry = result.GetDirectoryEntry();
        string displayName = directoryEntry.Properties["displayName"][0].ToString();
        string firstName = directoryEntry.Properties["givenName"][0].ToString(); 
        string lastName = directoryEntry.Properties["sn"][0].ToString(); 
        string email = directoryEntry.Properties["mail"][0].ToString();
        TextBox1.Text = displayName.ToString();