Неудается преобразовать тип System.Net.NetworkCredentian to System.Net.ICredentialsByHost

private void OnApplicationQuit()
        {
            MailAddress From = new MailAddress("mail@yandex.ru");
            MailAddress To = new MailAddress("mail@yandex.ru");
            MailMessage msg = new MailMessage(From, To);
            msg.Subject = "Subject";
            msg.Body = "<center>Application Quit</center>";
            msg.IsBodyHtml = true;
            SmtpClient client = new SmtpClient("smtp.yandex.ru", 587);
            client.Credentials = new NetworkCredential("mail@mail.ru", "password");
            client.EnableSsl = true;
            client.Send(msg);
        }

            MailAddress AddressFromEmail = new MailAddress("email");
 
            MailAddress AddressToEmail = new MailAddress("email");
 
            MailMessage CreateMessage = new MailMessage(AddressFromEmail, AddressToEmail);
 
            CreateMessage.Subject = "Тест";
 
            CreateMessage.Body = "<h2>Письмо-тест работы smtp-клиента</h2>";
 
            CreateMessage.IsBodyHtml = true;
 
            SmtpClient OpenSMTPForSendMessage = new SmtpClient("smtp.live.com", 25);
 
            OpenSMTPForSendMessage.Credentials = new NetworkCredential("email", "password");
 
            OpenSMTPForSendMessage.EnableSsl = true;
 
            OpenSMTPForSendMessage.Send(CreateMessage);

client.Credentials =(System.Net.ICredentialsByHost)new System.Net.NetworkCredential("Email", "password");