Embed image to email message in System.Web.Mail.MailMessage
<p>I want to send email using System.Web.Mail.MailMessage along with System.Web.Mail.SmtpMail class.
I know that this is a deprecated class but using System.Net.Mail is not an option for me.</p>

<p>So far I am able to send html formatted mail but I am not able to <strong>embed image to my email</strong> while sending.</p>

<p>This is what I've tried so far;</p>

<pre><code>private static void SendMailMethod(string mailServer, int mailServerPort, string userName, string password)
    {
        const string SMTP_SERVER = "http://schemas.microsoft.com/cdo/configuration/smtpserver";
        const string SMTP_SERVER_PORT =
            "http://schemas.microsoft.com/cdo/configuration/smtpserverport";

        const string SEND_USING = "http://schemas.microsoft.com/cdo/configuration/sendusing";

        const string SMTP_USE_SSL = "http://schemas.microsoft.com/cdo/configuration/smtpusessl";


        const string SMTP_AUTHENTICATE =
           "http://schemas.microsoft.com/cdo/configuration/smtpauthenticate";


        const string SEND_USERNAME =
            "http://schemas.microsoft.com/cdo/configuration/sendusername";
        const string SEND_PASSWORD =
            "http://schemas.microsoft.com/cdo/configuration/sendpassword";


        var mailMessage = new System.Web.Mail.MailMessage();

        mailMessage.Fields[SMTP_SERVER] = mailServer;
        mailMessage.Fields[SMTP_SERVER_PORT] = mailServerPort;
        mailMessage.Fields[SEND_USING] = 2;
        mailMessage.Fields[SMTP_USE_SSL] = false;
        mailMessage.Fields[SMTP_AUTHENTICATE] = 0;
        mailMessage.Fields[SEND_USERNAME] = userName;
        mailMessage.Fields[SEND_PASSWORD] = password;

        mailMessage.From = "abc@xyz.com";
        mailMessage.To = "abc@xyz.com";
        mailMessage.Subject = "Test mail:";
        mailMessage.BodyFormat = MailFormat.Html;

        var mailAttachment = new MailAttachment("E:\\imageToEmbed.jpg");
        mailMessage.Attachments.Add(mailAttachment);
        mailMessage.Attachments.Add(new MailAttachment("E:\\TestAttachmentFile.txt"));

        var htmlBody =
            "&lt;!DOCTYPE html PUBLIC \" -//W3C//DTD XHTML 1.0 Transitional//EN\" \"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd\"&gt;" +
            "&lt;html xmlns = \"http://www.w3.org/1999/xhtml\" &gt;" +
            " &lt;head &gt;" +
            "&lt;meta http - equiv = \"content-type\" content = \"text/html; charset=UTF-8\" /&gt;" +
            "&lt;/head &gt;" +
            "&lt;body style = \"font-family: Segoe UI; text-align:left;\" &gt;" +
            "Following is an embedded image:" +
            "&lt;br /&gt;" +
            "&lt;img alt = \"\" src = \"imageToEmbed.jpg\" /&gt;" +
            "&lt;/body &gt;" +
            "&lt;/html &gt;";

        mailMessage.Body = htmlBody;

        try
        {
            SmtpMail.Send(mailMessage);

            Console.WriteLine("Mail sent");
        }
        catch (Exception ex)
        {
            Console.WriteLine("Error:" + ex.ToString());
            throw ex;
        }
    }
</code></pre>

<p>This code sends email but instead of showing image, the mail shows small square with a cross in it.
How can I embed this "imageToEmbed.jpg" to my email. </p>