Image not displayed in Outlook in ASP

Question

After sending an email the logo is not displayed in Outlook but it works in Gmail.

I found that in the inspect element that the image src is changed into blockedimagesrc

In my Controller :

var NotifyCompany = new NotifyCompany()
{
   Email = model.regE,
   EmailTo = contact.GetPropertyValue<string>("email"),
   DateRegistered = DateTime.UtcNow
};
EmailHelpers.SendEmail(NotifyCompany, "NotifyCompany", "New Client Registered");

Helpers :

public static ActionResponse SendEmail(IEmail model, string emailTemplate, string subject, List<HttpPostedFileBase> files = null)
{
    try
    {
        var template =
        System.IO.File.ReadAllText(HttpContext.Current.Server.MapPath(string.Format("~/Templates/{0}.cshtml", emailTemplate)));
        var body = Razor.Parse(template, model);

        var attachments = new List<Attachment>();
        if (files != null && files.Any())
        {
            foreach (var file in files)
            {
                var att = new Attachment(file.InputStream, file.FileName);
                attachments.Add(att);
            }
        }

        var email = Email
        .From(ConfigurationManager.AppSettings["Email:From"], "myWebsiteEmail")
        .To(model.EmailTo)
        .Subject(subject)
        .Attach(attachments)
        .Body(body).BodyAsHtml();

        email.Send();
        return new ActionResponse()
        {
            Success = true
        };
    }
    catch (Exception ex)
    {
        return new ActionResponse()
        {
            Success = false,
            ErrorMessage = ex.Message
        };
    }
}

In my Email Template :

<img src="/mysite.com/image/logo.png"/>

Any help would be appreciated.

Answer 1

Outlook web access will block any images by default - only if the user chooses to display/download images these will be displayed/downloaded. I am not sure if it is possible to adjust the default behavior by using office 365 admincenter or the OWA settings.

Some time ago it was possible to work around this by using it as a background image inside a table>tr>td cell background-image css property.

EDIT

Checked a recent project of myself, where we are sending notification mails about tickets. The site logo is displayed correctly in outlook/owa - without adding the recipient to the trusted list:

            using (MailMessage mm = new MailMessage(sender, header.RecipientAddress, header.Subject, header.Body))
            {
                mm.Body = header.Body;
                mm.BodyEncoding = Encoding.UTF8;
                mm.DeliveryNotificationOptions = DeliveryNotificationOptions.OnFailure;
                mm.Priority = priority == IntMailPriority.High ? MailPriority.High : MailPriority.Normal;
                mm.IsBodyHtml = bodyIsHtml;

                // logo
                if (bodyIsHtml)
                {
                    AlternateView htmlView = AlternateView.CreateAlternateViewFromString(header.Body, Encoding.UTF8, "text/html");

                    string logoPath = $"{AppDomain.CurrentDomain.BaseDirectory}\\images\\logo_XXX.png";
                    LinkedResource siteLogo = new LinkedResource(logoPath)
                        {
                            ContentId = "logoId"
                        };
                    htmlView.LinkedResources.Add(siteLogo);
                    mm.AlternateViews.Add(htmlView);
                }

                // create smtpclient
                SmtpClient smtpClient = new SmtpClient(smtpSettings.ServerAddress, smtpSettings.Port)
                                    {
                                        Timeout = 30000,
                                        DeliveryMethod = SmtpDeliveryMethod.Network
                                    };
                // set relevant smtpclient settings 
                if (smtpSettings.UseTlsSsl)
                {
                    smtpClient.EnableSsl = true;

                    // needed for invalid certificates
                    ServicePointManager.ServerCertificateValidationCallback = delegate { return true; };
                }
                if (smtpSettings.UseAuth)
                {
                    smtpClient.UseDefaultCredentials = false;

                    NetworkCredential smtpAuth = new NetworkCredential { UserName = smtpSettings.Username, Password = smtpSettings.Password };
                    smtpClient.Credentials = smtpAuth;
                }

                smtpClient.Timeout = smtpSettings.SendingTimeout * 1000;

                // finally sent mail \o/ :)
                try
                {
                    smtpClient.Send(mm);
                }
                catch (SmtpException exc)
                {
                    throw new ProgramException(exc, exc.Message);
                }
                catch (InvalidOperationException exc)
                {
                    throw new ProgramException(exc, exc.Message);
                }
                catch (AuthenticationException exc)
                {
                    throw new ProgramException(exc, exc.Message);
                }
            }

Afterwards the logo is referred to as

<IMG alt="Intex Logo" src="cid:logoId">

inside the generated html.