C#

It was not possible to connect to the redis server(s); to create a disconnected multiplexer, disable AbortOnConnectFail. UnableToResolvePhysicalConnection on PING

StackExchange.Redis.RedisConnectionException: It was not possible to connect to the redis server(s); to create a disconnected multiplexer, disable AbortOnConnectFail. UnableToResolvePhysicalConnection on PING
   at StackExchange.Redis.ConnectionMultiplexer.ConnectImpl(Func`1 multiplexerFactory, TextWriter log)
   at StackExchange.Redis.ConnectionMultiplexer.Connect(String configuration, TextWriter log)
   at StackExchangeApplication.Source.Service.RedisService..ctor()
   at StackExchangeApplication.Source.Service.RedisService.get_GetInstance()
   at StackExchangeApplication.RedisHelper.GetStringValue(GetValueRequestMessage requestMessage)

public class RedisService
{

        public static ConnectionMultiplexer _connection;
        public static IDatabase _redisDatabase;

        static RedisService()
        {
            _connection = ConnectionMultiplexer.Connect("localhost");
            _redisDatabase = _connection.GetDatabase();
        }
     
       public void AddStringKeyValue(string key, string value, int expireInMinute)
        {
            bool result = _redisDatabase.StringSet(key, value, TimeSpan.FromMinutes(expireInMinute), When.Always,
                CommandFlags.None);

            if (!result)
            {
                throw new Exception("Failed To add key value in Redis server Key : " + key + ", Value : " + value);
            }
        }

        public string GetStringValue(string key)
        {
            string value = _redisDatabase.StringGet(key);
            return value;
        }

}

static public void refresh(DataGridView datagridview)
            
        {
            try
            {
                if (Connection.State == ConnectionState.Closed)
                    Connection.Open();
                MySqlDataAdapter dataadapter = new MySqlDataAdapter("SELECT * FROM suTable", Connection);
                DataTable dt = new DataTable();
                dataadapter.Fill(dt);
                datagridview.DataSource = dt;
              
            }
            catch (MySqlException Exception)
            {
                MessageBox.Show(Exception.ToString());
            }
            finally
            {
                Connection.Close();
            }

try
        {
            SmtpClient client=new SmtpClient("smtp.gmail.com",587);
            MailMessage message = new MailMessage();
            message.From = new MailAddress(txtemail.Text);
            message.To.Add(txtreciever.Text);
            message.Body = txtbody.Text;
            message.Subject = txtsubject.Text;
            client.UseDefaultCredentials = false;
            client.EnableSsl = true;

            if (txtattachment.Text != "")
            {
                message.Attachments.Add(new Attachment(txtattachment.Text));

            }
            client.Credentials = new System.Net.NetworkCredential(txtemail.Text, txtpassword.Text);
            client.Send(message);
            message = null;
            MessageBox.Show("Message Sent");
        }
        catch(Exception ex)
        {
            MessageBox.Show( "Failed to Send Message");
        }