1 using System;
 2 using System.Collections.Generic;
 3 using System.ComponentModel;
 4 using System.Data;
 5 using System.Drawing;
 6 using System.Linq;
 7 using System.Text;
 8 using System.Windows.Forms;
 9 using Outlook = Microsoft.Office.Interop.Outlook;
10 
11 namespace SendMailByOutlook
12 {
13     public partial class Form1 : Form
14     {
15         public Form1()
16         {
17             InitializeComponent();
18         }
19 
20         private void button1_Click(object sender, EventArgs e)
21         {
22             Outlook.Application olApp = new Outlook.Application();
23             Outlook.MailItem mailItem = (Outlook.MailItem)olApp.CreateItem(Outlook.OlItemType.olMailItem);
24             mailItem.To = "xyz@hotmail.com";
25             mailItem.Subject = "A test";
26             mailItem.BodyFormat = Outlook.OlBodyFormat.olFormatHTML;
27             mailItem.HTMLBody = "Hello world";
28             ((Outlook._MailItem)mailItem).Send();
29 
30             mailItem = null;
31             olApp = null;
32             MessageBox.Show("Mail has been sent successfully!");
33             
34             
35         }
36     }
37 }