C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.SessionState;
using System.Threading;
using System.Threading.Tasks;
using System.Net;

using Telegram.Bot;
using Telegram.Bot.Args;
using Telegram.Bot.Types;
using Telegram.Bot.Types.Enums;
using Telegram.Bot.Types.ReplyMarkups;
using System.IO;



namespace EC
{

public class Global : System.Web.HttpApplication
    {

        Telegram.Bot.TelegramBotClient Bot = new TelegramBotClient("xxxxxx");

        protected void Application_Start()
        {
            ServicePointManager.Expect100Continue = true;
            ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12;

            Bot.OnMessage += Bot_OnMessage;
            Bot.OnUpdate += Bot_OnUpdate;
            Bot.StartReceiving();

        }

        private void Bot_OnMessage(object sender, MessageEventArgs messageEventArgs)
        {
            var message = messageEventArgs.Message;

            if (message == null || message.Type != MessageType.Text) return;

            if (message.Text.Contains("/start"))
            {
                string Str = "Start Received";

                Bot.SendTextMessageAsync(message.Chat.Id, Str);

            }
            else if (message.Text.Contains("/Stop"))
            {
                string Str = "Stop Received";
                Bot.SendTextMessageAsync(message.Chat.Id, Str);
            }
        }
 }

string domain = "LDAP://DC=MyCompany,DC=com";
string serverName = "192.168.30.10";
string ou = "OU=OrgUnit-Test-1,DC=MyCompany,DC=com";

<pre>public List<ActiveDirectoryUser> GetAllUsersInGroup(string domainName, string groupName)
{
    List<ActiveDirectoryUser> results = new List<ActiveDirectoryUser>();

    using (var context = new PrincipalContext(ContextType.Domain, domainName))
    {
        using (var group = GroupPrincipal.FindByIdentity(context, groupName))
        {
            if (group != null)
            {
                var users = group.GetMembers(true).ToList();
                foreach (UserPrincipal user in users)
                {
                    var adu = new ActiveDirectoryUser(user.DisplayName, user.UserPrincipalName, user.GivenName, user.Surname, user.EmailAddress, user.Enabled.Value);
                    results.Add(adu);
                }
            }
        }
    }

    return results;
}