Automatically sending emails...

Quartz consists of 3 primary components - a job, a trigger and a scheduler

using Quartz;
using System;
using System.Net;
using System.Net.Mail;

namespace ScheduledTaskExample.ScheduledTasks
{
    public class EmailJob : IJob
    {
        public void Execute(IJobExecutionContext context)
        {
            using (var message = new MailMessage("user@gmail.com", "user@live.co.uk"))
            {
                message.Subject = "Test";
                message.Body = "Test at " + DateTime.Now;
                using (SmtpClient client = new SmtpClient
                {
                    EnableSsl = true,
                    Host = "smtp.gmail.com",
                    Port = 587,
                    Credentials = new NetworkCredential("user@gmail.com", "password")
                })
                {
                    client.Send(message);
                }
            }
        }
    }
}

using Quartz;
using Quartz.Impl;
using System;

namespace ScheduledTaskExample.ScheduledTasks
{
    public class JobScheduler
    {
        public static void Start()
        {
            IScheduler scheduler = StdSchedulerFactory.GetDefaultScheduler();
            scheduler.Start();

            IJobDetail job = JobBuilder.Create<EmailJob>().Build();

            ITrigger trigger = TriggerBuilder.Create()
                .WithDailyTimeIntervalSchedule
                  (s =>
                     s.WithIntervalInHours(24)
                    .OnEveryDay()
                    .StartingDailyAt(TimeOfDay.HourAndMinuteOfDay(0, 0))
                  )
                .Build();

            scheduler.ScheduleJob(job, trigger);
        }
    }
}