Sending e-mails with attachment in C#

In previous post we saw how to send e-mails using C# in few simple steps. Here we will see how to add attachments to our messages.

Know it:

System.Net.Mail.Attachment : Used to attach any file to our MailMessage.

GUI form:

Sending mails with attachments in C#.

Implement it:

using System;
using System.ComponentModel;
using System.Net.Mail;
using System.Windows.Forms;

namespace MailMe
    public partial class Form1 : Form
        public Form1()

            mailProviderList.SelectedIndex = 0;

        private void sendButton_Click(object sender, EventArgs e)
            //Fetch all message details from the form.
            string To = this.toTextbox.Text;
            string BCC = this.bccTextbox.Text;
            string CC = this.ccTextbox.Text;
            string Subject = this.subjectTextbox.Text;
            string Body = this.bodyTextbox.Text;

            //Fetch all attachment file paths from Attachment list.
            string[] Attachments = new string[this.attachmentListbox.Items.Count];
            this.attachmentListbox.Items.CopyTo(Attachments, 0);

            //Fetch the smtp server details
            string SelectedMailProvider = (string)this.mailProviderList.SelectedItem;
            string SmtpHost = "";
            int PORT = 587;
            switch (SelectedMailProvider)
                case "Gmail": SmtpHost = SmtpServer.Gmail;
                    PORT = (int)SmtpServer.PORT.Gmail;
                case "Hotmail": SmtpHost = SmtpServer.Hotmail;
                    PORT = (int)SmtpServer.PORT.Hotmail;
                case "Outlook": SmtpHost = SmtpServer.Outlook;
                    PORT = (int)SmtpServer.PORT.Outlook;
                case "Office365": SmtpHost = SmtpServer.Office365;
                    PORT = (int)SmtpServer.PORT.Office365;
                case "Yahoo Mail": SmtpHost = SmtpServer.YahooMail;
                    PORT = (int)SmtpServer.PORT.YahooMail;
                case "Yahoo Mail Plus": SmtpHost = SmtpServer.YahooMailPlus;
                    PORT = (int)SmtpServer.PORT.YahooMailPlus;
                case "Verizon": SmtpHost = SmtpServer.Verizon;
                    PORT = (int)SmtpServer.PORT.Verizon;

            //Fetch Authentication details
            string UserID = this.userIdTextbox.Text;
            string Password = this.passwordTextbox.Text;

                //Initializes a new SmtpClient.
                SmtpClient client = new SmtpClient(SmtpHost, PORT);
                client.EnableSsl = true;
                client.Credentials = new System.Net.NetworkCredential(UserID, Password);

                //client_SendCompleted method will be called after the email has been sent successfully.
                client.SendCompleted += client_SendCompleted;

                //Initializes new MailMessage.
                MailMessage msg = new MailMessage(UserID, To);

                //Add BCC list of the message.
                if (!string.IsNullOrEmpty(BCC))
                    string[] BccList = BCC.Split(',');
                    foreach (string bcc in BccList)

                //Add cc list of the message.
                if (!string.IsNullOrEmpty(CC))
                    string[] ccList = CC.Split(',');
                    foreach (string cc in ccList)

                //Add subject of the message.
                msg.Subject = Subject;

                //Add Body of the message.
                msg.Body = Body;

                //Add attachments to the message.
                foreach (string filePaths in Attachments)
                    msg.Attachments.Add(new Attachment(filePaths));

                //Sends the message in backgound.
                client.SendAsync(msg, null);

                MessageBox.Show("Please wait while sending...");
            catch (Exception er)
                MessageBox.Show("Unable to send mail.\nError:" + er.Message, "Error");

        void client_SendCompleted(object sender, AsyncCompletedEventArgs e)
            if (e.Error != null)
                MessageBox.Show("Unable to send email.\nError:" + e.Error.Message, "Error");
                MessageBox.Show("Mail sent successfully.");

        private void closeButton_Click(object sender, EventArgs e)
            //Closes the form.

        private void addAttachmentButton_Click(object sender, EventArgs e)
            OpenFileDialog FileChooser = new OpenFileDialog();
            FileChooser.Multiselect = true;
            FileChooser.Title = "Insert Attachments";
            DialogResult res = FileChooser.ShowDialog();

            if (res != System.Windows.Forms.DialogResult.Cancel)
                foreach (string filePath in FileChooser.FileNames)

        private void removeMenu_Click(object sender, EventArgs e)
            //Gets the selected index from attachment listbox and remove the element from the list.
            int SelectedIndex = this.attachmentListbox.SelectedIndex;

            if (SelectedIndex >= 0)

        private void removeAllMenu_Click(object sender, EventArgs e)
            //Clears all elements present in Attachment listbox

    /// A list of popular smtp server with their port.
    public class SmtpServer
        public const string Gmail = "";
        public const string Hotmail = "";
        public const string Outlook = "";
        public const string Office365 = "";
        public const string Verizon = "";
        public const string YahooMail = "";
        public const string YahooMailPlus = "";

        //Smtp servers PORT.
        public enum PORT
            Gmail = 587,
            Outlook = 587,
            Office365 = 587,
            Hotmail = 465,
            YahooMail = 465,
            YahooMailPlus = 465,
            Verizon = 587


Sending e mails with attachment in C#.

Download Exe
Download Full C# Project

Happy coding ;)
Any doubt or suggestion write here. I will try my best to help. Before posting your code you must escape it to view. To format your source code and use format highlighting, post your source code inside
< pre>< code >----Your Source Code---- < / code > < / pre > (Remove spaces from pre and code tags)


  1. How about putting some progress bar while sending the email? Also, it will be better if there is "Delete Attachment" as well. This can be considered as a base for future functionality upgrade. Good share...

    1. I have added an update to remove attachment. For the progress bar currently there isn't any methods provided with SmtpClient but still i am working over it.