/// <summary>
        /// This function will take a DL or Group name and return list of users
        /// </summary>
        /// <param name="groupName"></param>
        /// <returns></returns>
        public List <ADUserDetail> GetUserFromGroup(String groupName)
        {
            List <ADUserDetail> userlist = new List <ADUserDetail>();

            try
            {
                _directoryEntry = null;
                DirectorySearcher directorySearch = new DirectorySearcher(SearchRoot);
                directorySearch.Filter = "(&(objectClass=group)(SAMAccountName=" + groupName + "))";
                SearchResult results = directorySearch.FindOne();
                if (results != null)
                {
                    DirectoryEntry deGroup = new DirectoryEntry(results.Path);    //, LDAPUser, LDAPPassword);
                    System.DirectoryServices.PropertyCollection pColl = deGroup.Properties;
                    int count = pColl["member"].Count;


                    for (int i = 0; i < count; i++)
                    {
                        string   respath      = results.Path;
                        string[] pathnavigate = respath.Split("CN".ToCharArray());
                        respath = pathnavigate[0];
                        string objpath = pColl["member"][i].ToString();
                        string path    = respath + objpath;


                        DirectoryEntry user    = new DirectoryEntry(path); //, LDAPUser, LDAPPassword);
                        ADUserDetail   userobj = ADUserDetail.GetUser(user);
                        userlist.Add(userobj);
                        user.Close();
                    }
                }
                return(userlist);
            }
            catch (Exception ex)
            {
                return(userlist);
            }
        }
        internal ADUserDetail GetUserByFullName(String userName)
        {
            try
            {
                _directoryEntry = null;
                DirectorySearcher directorySearch = new DirectorySearcher(SearchRoot);
                directorySearch.Filter = "(&(objectClass=user)(cn=" + userName + "))";
                SearchResult results = directorySearch.FindOne();

                if (results != null)
                {
                    DirectoryEntry user = new DirectoryEntry(results.Path);    // LDAPUser, LDAPPassword);
                    return(ADUserDetail.GetUser(user));
                }
                else
                {
                    return(null);
                }
            }
            catch (Exception ex)
            {
                return(null);
            }
        }