Develop Reference

The image is not displayed when sent to email

string html = "<img src=data:image/png;base64,i0KGgAD34DtaA..........*>"; //*very long
SensMail(mailaddress,html, System.Text.Encoding.UTF8);
public static void SensMail(string sendTo, string body, System.Text.Encoding enCode)
{
string emailaddress = "mail#gmail.com";
string password = "it's secret";
MailMessage mail = new MailMessage();
SmtpClient SmtpServer = new SmtpClient();
mail.From = new MailAddress(sendTo);
mail.To.Add(sendTo);
mail.BodyEncoding = enCode;
mail.IsBodyHtml = true;
mail.Subject = "subject";
mail.Body = body;
SmtpServer.UseDefaultCredentials = false;
NetworkCredential NetworkCred = new NetworkCredential(emailaddress,password);
SmtpServer.Credentials = NetworkCred;
SmtpServer.EnableSsl = true;
SmtpServer.Port = 587;
SmtpServer.Host = "smtp.gmail.com";
SmtpServer.Send(mail);
}
Why is the image not displayed ??
I tried to send to two different email providers, without success.
Is this happening for security reasons?
How can this problem be solved?
In HTML it does work and you see the image.

Outlook doesn't understand base64 images. There are two possible ways:
Upload the image file to any web server and then use the image URL in the HTML body for that image. Be aware, Outlook may block external links (even for images) automatically.
You may add an image file as an attachment and then use the cid prefix for the img tag. See Send inline image in email for more information.

C# SMTP MailMessage receiving error "5.7.57 SMTP; Client was not authenticated to send anonymous mail during MAIL FROM"

The code I currently have is:
public void SendEmail(string to, string cc, string bcc, string subject, string body, string attachmentPath = "", System.Net.Mail.MailPriority emailPriority = MailPriority.Normal, BodyType bodyType = BodyType.HTML)
{
try
{
var client = new System.Net.Mail.SmtpClient();
{
client.Host = "smtp-mail.outlook.com";
client.Port = 587;
client.UseDefaultCredentials = false;
client.EnableSsl = true;
client.DeliveryMethod = System.Net.Mail.SmtpDeliveryMethod.Network;
client.Credentials = new NetworkCredential("[my company email]", "[my password]");
client.Timeout = 600000;
}
MailMessage mail = new MailMessage("[insert my email here]", to);
mail.Subject = subject;
mail.Body = body;
client.Send(mail);
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
The email address I'm trying to send to is hosted on Office 365's Outlook. We might have to change the specific address later, but they'd likely be configured the same.
However, whenever I try to run the client.Send(mail); command, I receive the same error. The full text of the error is:
The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.7.57 SMTP; Client was not authenticated to send anonymous mail during MAIL FROM
I've tried a few different things, like switching the port between 25 and 587, changing the host to Office365's, or toggling UseDefaultCredentials and EnableSssl to true or false. But I always see the same error. Is there something else I'm missing?

I found an example code block elsewhere on this site and replacing everything I had with it made the difference.
The function name and parameters were the same, but here's what I replaced the body of it with.
var _mailServer = new SmtpClient();
_mailServer.UseDefaultCredentials = false;
_mailServer.Credentials = new NetworkCredential("my email", "my password");
_mailServer.Host = "smtp.office365.com";
_mailServer.TargetName = "STARTTLS/smtp.office365.com";
_mailServer.Port = 587;
_mailServer.EnableSsl = true;
var eml = new MailMessage();
eml.Sender = new MailAddress("my email");
eml.From = eml.Sender;
eml.To.Add(new MailAddress(to));
eml.Subject = subject;
eml.IsBodyHtml = (bodyType == BodyType.HTML);
eml.Body = body;
_mailServer.Send(eml);
I don't know for certain but I think that replacing the Host value with the smtp Office 365 link rather than an outlook one, as well as remembering to add a Target Name which I did not have before, both did the trick and solved the authorization issue (I had previously confirmed it wasn't a credentials issue with our tech support).

Why image is not displaying in html mail in gmail?

I'm trying to add an image in HTML mail. It is displaying when I save that body as html file, but when I send that html body as an email through GMail, the image is not displaying. Can anyone tell me the reason?
I set the source of the image in this way:
var image = body.GetElementsByTagName("img");
string imageAttachmentPath = Path.Combine(Globals.NotificationTemplatesPath, "Header.png");
foreach (XmlElement img in image)
{
img.SetAttribute("src", imageAttachmentPath);
break;
}
//thats the method in which i am sending email.
public static void SendMessageViaEmailService(string from,
string sendTo,
string carbonCopy,
string blindCarbonCopy,
string subject,
string body,
bool isBodyHtml,
string imageAttachmentPath,
Hashtable images,
List<string> attachment,
string title = null,
string embeddedImages = null)
{
Attachment image = new Attachment(imageAttachmentPath);
MailMessage msg = new MailMessage();
msg.IsBodyHtml = true; // email body will allow html elements
msg.From = new MailAddress(from, "Admin"); // setting the Sender Email ID
msg.To.Add(sendTo); // adding the Recipient Email ID
if (!string.IsNullOrEmpty(carbonCopy)) // add CC email ids if supplied.
msg.CC.Add(carbonCopy);
msg.Subject = subject; //setting email subject and body
msg.Body = body;
msg.Attachments.Add(image);
//create a Smtp Mail which will automatically get the smtp server details
//from web.config mailSettings section
SmtpClient SmtpMail = new SmtpClient();
SmtpMail.Host = "smtp.gmail.com";
SmtpMail.Port = 587;
SmtpMail.EnableSsl = true;
SmtpMail.UseDefaultCredentials = false;
SmtpMail.Credentials = new System.Net.NetworkCredential(from, "password");
// sending the message.
try
{
SmtpMail.Send(msg);
}
catch (Exception ex) { }
}

More than likely your image SRC attribute is not an absolute, publicly-accessible URI. Any file-system or local URI's will not show the image in the email.
Specifically, these will not work:
c://test.png
test.png
/folder/test.png
http://localhost/test.png
http://internaldomain/test.png
Ensure that your image urls are
absolute (i.e. start with the protocol like http://)
includes a full path to the image
the domain is a public domain

Try the code part from this thread:
// creating the attachment
System.Net.Mail.Attachment inline = new System.Net.Mail.Attachment(#"c:\\test.png");
inline.ContentDisposition.Inline = true;
// sending the message
MailMessage email = new MailMessage();
// set the information of the message (subject, body ecc...)
// send the message
System.Net.Mail.SmtpClient smtp = new System.Net.Mail.SmtpClient("localhost");
smtp.Send(email);
email.Dispose();

C# Sending .htm email Template

Using the simple SMTP C# code below to send an email, how can i send an email template?
System.Net.Mail.MailMessage message = new System.Net.Mail.MailMessage();
message.To.Add(toEmailAddress);
message.Subject = "subject";
message.From = new System.Net.Mail.MailAddress(from);
message.Body = "http://www.yoursite.com/email.htm";
message.IsBodyHtml = true;
System.Net.Mail.SmtpClient smtp = new System.Net.Mail.SmtpClient("server");
smtp.Send(message);
Currently, as expected the received email just contains the URL for the template. how can i get it to send the template?

System.Net.WebClient client = new System.Net.WebClient();
string html = client.DownloadString("http://www.yoursite.com/email.htm");
System.Net.Mail.MailMessage message = new System.Net.Mail.MailMessage();
message.To.Add(toEmailAddress);
message.Subject = "subject";
message.From = new System.Net.Mail.MailAddress(from);
message.Body = html;
message.IsBodyHtml = true;
System.Net.Mail.SmtpClient smtp = new System.Net.Mail.SmtpClient("server");
smtp.Send(message);

Your question is actually about reading a string from url and one of the possible answers is:
var url = "http://www.yoursite.com/email.htm";
var body = "";
using(var client = new WebClient()) {
body = client.DownloadString(url);
}

If the file is local, instead of using a download, you can simply read it in using System.IO, such as
string html;
System.IO.StreamReader fstream;
fstream = File.OpenText("yourpathgoeshere.html");
html = fstream.ReadToEnd();
fstream.Close();
after this, just assign the rest of the properties as suggested in the other posts. If the html file you're after is stored locally, this is probably better, or if it will be accessed frequently, it may be a better idea to store it locally and use this method.
note, you will need to import System.IO for this to work correctly.

Sending email with attachments from C#, attachments arrive as Part 1.2 in Thunderbird

I have a C# application which emails out Excel spreadsheet reports via an Exchange 2007 server using SMTP. These arrive fine for Outlook users, but for Thunderbird and Blackberry users the attachments have been renamed as "Part 1.2".
I found this article which describes the problem, but doesn't seem to give me a workaround. I don't have control of the Exchange server so can't make changes there. Is there anything I can do on the C# end? I have tried using short filenames and HTML encoding for the body but neither made a difference.
My mail sending code is simply this:
public static void SendMail(string recipient, string subject, string body, string attachmentFilename)
{
SmtpClient smtpClient = new SmtpClient();
NetworkCredential basicCredential = new NetworkCredential(MailConst.Username, MailConst.Password);
MailMessage message = new MailMessage();
MailAddress fromAddress = new MailAddress(MailConst.Username);
// setup up the host, increase the timeout to 5 minutes
smtpClient.Host = MailConst.SmtpServer;
smtpClient.UseDefaultCredentials = false;
smtpClient.Credentials = basicCredential;
smtpClient.Timeout = (60 * 5 * 1000);
message.From = fromAddress;
message.Subject = subject;
message.IsBodyHtml = false;
message.Body = body;
message.To.Add(recipient);
if (attachmentFilename != null)
message.Attachments.Add(new Attachment(attachmentFilename));
smtpClient.Send(message);
}
Thanks for any help.

Simple code to send email with attachement.
source: http://www.coding-issues.com/2012/11/sending-email-with-attachments-from-c.html
using System.Net;
using System.Net.Mail;
public void email_send()
{
MailMessage mail = new MailMessage();
SmtpClient SmtpServer = new SmtpClient("smtp.gmail.com");
mail.From = new MailAddress("your mail#gmail.com");
mail.To.Add("to_mail#gmail.com");
mail.Subject = "Test Mail - 1";
mail.Body = "mail with attachment";
System.Net.Mail.Attachment attachment;
attachment = new System.Net.Mail.Attachment("c:/textfile.txt");
mail.Attachments.Add(attachment);
SmtpServer.Port = 587;
SmtpServer.Credentials = new System.Net.NetworkCredential("your mail#gmail.com", "your password");
SmtpServer.EnableSsl = true;
SmtpServer.Send(mail);
}

Explicitly filling in the ContentDisposition fields did the trick.
if (attachmentFilename != null)
{
Attachment attachment = new Attachment(attachmentFilename, MediaTypeNames.Application.Octet);
ContentDisposition disposition = attachment.ContentDisposition;
disposition.CreationDate = File.GetCreationTime(attachmentFilename);
disposition.ModificationDate = File.GetLastWriteTime(attachmentFilename);
disposition.ReadDate = File.GetLastAccessTime(attachmentFilename);
disposition.FileName = Path.GetFileName(attachmentFilename);
disposition.Size = new FileInfo(attachmentFilename).Length;
disposition.DispositionType = DispositionTypeNames.Attachment;
message.Attachments.Add(attachment);
}
BTW, in case of Gmail, you may have some exceptions about ssl secure or even port!
smtpClient.EnableSsl = true;
smtpClient.Port = 587;

Here is a simple mail sending code with attachment
try
{
SmtpClient mailServer = new SmtpClient("smtp.gmail.com", 587);
mailServer.EnableSsl = true;
mailServer.Credentials = new System.Net.NetworkCredential("myemail#gmail.com", "mypassword");
string from = "myemail#gmail.com";
string to = "reciever#gmail.com";
MailMessage msg = new MailMessage(from, to);
msg.Subject = "Enter the subject here";
msg.Body = "The message goes here.";
msg.Attachments.Add(new Attachment("D:\\myfile.txt"));
mailServer.Send(msg);
}
catch (Exception ex)
{
Console.WriteLine("Unable to send email. Error : " + ex);
}
Read more Sending emails with attachment in C#

Completing the solution of Ranadheer, using Server.MapPath to locate the file
System.Net.Mail.Attachment attachment;
attachment = New System.Net.Mail.Attachment(Server.MapPath("~/App_Data/hello.pdf"));
mail.Attachments.Add(attachment);

private void btnSent_Click(object sender, EventArgs e)
{
try
{
MailMessage mail = new MailMessage();
SmtpClient SmtpServer = new SmtpClient("smtp.gmail.com");
mail.From = new MailAddress(txtAcc.Text);
mail.To.Add(txtToAdd.Text);
mail.Subject = txtSub.Text;
mail.Body = txtContent.Text;
System.Net.Mail.Attachment attachment;
attachment = new System.Net.Mail.Attachment(txtAttachment.Text);
mail.Attachments.Add(attachment);
SmtpServer.Port = 587;
SmtpServer.Credentials = new System.Net.NetworkCredential(txtAcc.Text, txtPassword.Text);
SmtpServer.EnableSsl = true;
SmtpServer.Send(mail);
MessageBox.Show("mail send");
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
}
private void button1_Click(object sender, EventArgs e)
{
MailMessage mail = new MailMessage();
openFileDialog1.ShowDialog();
System.Net.Mail.Attachment attachment;
attachment = new System.Net.Mail.Attachment(openFileDialog1.FileName);
mail.Attachments.Add(attachment);
txtAttachment.Text =Convert.ToString (openFileDialog1.FileName);
}

I've made a short code to do that and I want to share it with you.
Here the main code:
public void Send(string from, string password, string to, string Message, string subject, string host, int port, string file)
{
MailMessage email = new MailMessage();
email.From = new MailAddress(from);
email.To.Add(to);
email.Subject = subject;
email.Body = Message;
SmtpClient smtp = new SmtpClient(host, port);
smtp.UseDefaultCredentials = false;
NetworkCredential nc = new NetworkCredential(from, password);
smtp.Credentials = nc;
smtp.EnableSsl = true;
email.IsBodyHtml = true;
email.Priority = MailPriority.Normal;
email.BodyEncoding = Encoding.UTF8;
if (file.Length > 0)
{
Attachment attachment;
attachment = new Attachment(file);
email.Attachments.Add(attachment);
}
// smtp.Send(email);
smtp.SendCompleted += new SendCompletedEventHandler(SendCompletedCallBack);
string userstate = "sending ...";
smtp.SendAsync(email, userstate);
}
private static void SendCompletedCallBack(object sender,AsyncCompletedEventArgs e) {
string result = "";
if (e.Cancelled)
{
MessageBox.Show(string.Format("{0} send canceled.", e.UserState),"Message",MessageBoxButtons.OK,MessageBoxIcon.Information);
}
else if (e.Error != null)
{
MessageBox.Show(string.Format("{0} {1}", e.UserState, e.Error), "Message", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
else {
MessageBox.Show("your message is sended", "Message", MessageBoxButtons.OK, MessageBoxIcon.Information);
}
}
In your button do stuff like this
you can add your jpg or pdf files and more .. this is just an example
using (OpenFileDialog attachement = new OpenFileDialog()
{
Filter = "Exel Client|*.png",
ValidateNames = true
})
{
if (attachement.ShowDialog() == DialogResult.OK)
{
Send("yourmail#gmail.com", "gmail_password",
"tomail#gmail.com", "just smile ", "mail with attachement",
"smtp.gmail.com", 587, attachement.FileName);
}
}

Try this:
private void btnAtt_Click(object sender, EventArgs e) {
openFileDialog1.ShowDialog();
Attachment myFile = new Attachment(openFileDialog1.FileName);
MyMsg.Attachments.Add(myFile);
}

I tried the code provided by Ranadheer Reddy (above) and it worked great. If you’re using a company computer that has a restricted server you may need to change the SMTP port to 25 and leave your username and password blank since they will auto fill by your admin.
Originally, I tried using EASendMail from the nugent package manager, only to realize that it’s a pay for version with 30-day trial. Don’t waist your time with it unless you plan on buying it. I noticed the program ran much faster using EASendMail, but for me, free trumped fast.
Just my 2 cents worth.

Use this method it under your email service it can attach any email body and attachments to Microsoft outlook
using Outlook = Microsoft.Office.Interop.Outlook; // Reference Microsoft.Office.Interop.Outlook from local or nuget if you will user a build agent later
try {
var officeType = Type.GetTypeFromProgID("Outlook.Application");
if(officeType == null) {//outlook is not installed
return new PdfErrorResponse {
ErrorMessage = "System cant start Outlook!, make sure outlook is installed on your computer."
};
} else {
// Outlook is installed.
// Continue your work.
Outlook.Application objApp = new Outlook.Application();
Outlook.MailItem mail = null;
mail = (Outlook.MailItem)objApp.CreateItem(Outlook.OlItemType.olMailItem);
//The CreateItem method returns an object which has to be typecast to MailItem
//before using it.
mail.Attachments.Add(attachmentFilePath,Outlook.OlAttachmentType.olEmbeddeditem,1,$"Attachment{ordernumber}");
//The parameters are explained below
mail.To = recipientEmailAddress;
//mail.CC = "con#def.com";//All the mail lists have to be separated by the ';'
//To send email:
//mail.Send();
//To show email window
await Task.Run(() => mail.Display());
}
} catch(System.Exception) {
return new PdfErrorResponse {
ErrorMessage = "System cant start Outlook!, make sure outlook is installed on your computer."
};
}