SMTP HTML email not rendering HTML via Gmail email client - c#

I am sending an email via C# SMTP. It's a HTML email which separates lines by tags, e.g. :
Dear Test,A password request has been initiated for your
account. Please click this link....
This renders fine in an Outlook inbox, but in Gmail it seemingly ignores the tags:
Gmail
Outlook
Why isn't Gmail rendering the HTML? It's the same result via the web browser as the Android email client.
When I view the source of the Gmail email and download the .eml file from Gmail the email contains the br tags.
I tried replacing the br tags with line breaks, but when I do that the opposite happens - it doesn't render the line breaks in Outlook but it does render them in Gmail.
What's actually going on here and how can I satisfy all email clients?
Content-Type: text/html; charset="utf-8"
Content-Transfer-Encoding: quoted-printable
Here is my C# for generating the emails:
var mailMessage = new MailMessage
{
Subject = subject,
BodyEncoding = Encoding.UTF8,
From = new MailAddress(EmailFrom),
IsBodyHtml = true
};
var htmlView = AlternateView.CreateAlternateViewFromString(body.ReplaceLineBreaksWithHtmlLineBreak(), new ContentType("text/html"));
htmlView.ContentType.CharSet = Encoding.UTF8.WebName;
mailMessage.AlternateViews.Add(htmlView);
var plainView = AlternateView.CreateAlternateViewFromString(body.StripHtml(), new ContentType("text/plain"));
plainView.ContentType.CharSet = Encoding.UTF8.WebName;
mailMessage.AlternateViews.Add(plainView);
For the HTML email, I replace line breaks in my template string with br tags. For the plain text view, any HTML is stripped out.
UPDATE:
It turns out on my plaintext view I was accidentally stripping out the line breaks. This solves the problem but another question I have is why does Gmail seemingly only render the plaintext version of the email?

Related

Send a Email with an Image inside the string html body [duplicate]

I'm trying to send a multipart/related html email with embedded gif images. This email is generated using Oracle PL/SQL. My attempts have failed, with the image showing up as a red X (in Outlook 2007 and yahoo mail)
I've been sending html emails for some time, but my requirements are now to use several gif images in the email. I can store these on one of our web servers and just link to them, but many users email clients will not show them automatically and will need to either change settings or manually download them for each email.
So, my thoughts are to embed the image. My questions are:
What am I doing wrong here?
Is the embedding approach the correct one?
Any other options if I need to use more and more images? Attachments won't work, as the images are typically logos and icons that won't make sense out of the context of the message. Also, some elements of the email are links into an online system, so generating a static PDF and attaching won't work (to my knowledge anyway).
snippet:
MIME-Version: 1.0
To: me#gmail.com
BCC: me#yahoo.com
From: email#yahoo.com
Subject: Test
Reply-To: email#yahoo.com
Content-Type: multipart/related; boundary="a1b2c3d4e3f2g1"
--a1b2c3d4e3f2g1
content-type: text/html;
<html>
<head><title>My title</title></head>
<body>
<div style="font-size:11pt;font-family:Calibri;">
<p><IMG SRC="cid:my_logo" alt="Logo"></p>
... more html here ...
</div></body></html>
--a1b2c3d4e3f2g1
Content-Type: image/gif;
Content-ID:<my_logo>
Content-Transfer-Encoding: base64
Content-Disposition: inline
[base64 image data here]
--a1b2c3d4e3f2g1--
Many thanks.
BTW: Yes, I have verified that the base64 data is correct, as I can embed the image in the html itself (using same algo use for creating header data) and see image in Firefox/IE.
I should also note that this is NOT for spam, the emails are sent to specific clients who are expecting it daily. The content is data-driven, and not adverts.
Try to insert it directly, this way you can insert multiple images at various locations in the email.
<img src="data:image/jpg;base64,{{base64-data-string here}}" />
And to make this post usefully for others to:
If you don't have a base64-data string, create one easily at:
http://www.motobit.com/util/base64-decoder-encoder.asp from a image file.
Email source code looks something like this, but i really cant tell you what that boundary thing is for:
To: email#email.de
Subject: ...
Content-Type: multipart/related;
boundary="------------090303020209010600070908"
This is a multi-part message in MIME format.
--------------090303020209010600070908
Content-Type: text/html; charset=ISO-8859-15
Content-Transfer-Encoding: 7bit
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=ISO-8859-15">
</head>
<body bgcolor="#ffffff" text="#000000">
<img src="cid:part1.06090408.01060107" alt="">
</body>
</html>
--------------090303020209010600070908
Content-Type: image/png;
name="moz-screenshot.png"
Content-Transfer-Encoding: base64
Content-ID: <part1.06090408.01060107>
Content-Disposition: inline;
filename="moz-screenshot.png"
[base64 image data here]
--------------090303020209010600070908--
//EDIT: Oh, i just realize if you insert the first code snippet from my post to write an email with thunderbird, thunderbird automatically changes the html code to look pretty much the same as the second code in my post.
The other solution is attaching the image as attachment and then referencing it html code using cid.
HTML Code:
<html>
<head>
</head>
<body>
<img width=100 height=100 id="1" src="cid:Logo.jpg">
</body>
</html>
C# Code:
EmailMessage email = new EmailMessage(service);
email.Subject = "Email with Image";
email.Body = new MessageBody(BodyType.HTML, html);
email.ToRecipients.Add("abc#xyz.com");
string file = #"C:\Users\acv\Pictures\Logo.jpg";
email.Attachments.AddFileAttachment("Logo.jpg", file);
email.Attachments[0].IsInline = true;
email.Attachments[0].ContentId = "Logo.jpg";
email.SendAndSaveCopy();
I don't find any of the answers here useful, so I am providing my solution.
The problem is that you are using multipart/related as the content type which is not good in this case. I am using multipart/mixed and inside it multipart/alternative (it works on most clients).
The message structure should be as follows:
[Headers]
Content-type:multipart/mixed; boundary="boundary1"
--boundary1
Content-type:multipart/alternative; boundary="boundary2"
--boundary2
Content-Type: text/html; charset=ISO-8859-15
Content-Transfer-Encoding: 7bit
[HTML code with a href="cid:..."]
--boundary2
Content-Type: image/png;
name="moz-screenshot.png"
Content-Transfer-Encoding: base64
Content-ID: <part1.06090408.01060107>
Content-Disposition: inline; filename="moz-screenshot.png"
[base64 image data here]
--boundary2--
--boundary1--
Then it will work
If it does not work, you may try one of these tools that convert the image to an HTML table (beware the size of your image though):
http://stylecampaign.com/blog/2009/12/bypass-image-blocking-by-converting-images-to-html/
http://neil.fraser.name/software/img2html/
I know this is an old post, but the current answers dont address the fact that outlook and many other email providers dont support inline images or CID images. The most effective way to place images in emails is to host it online and place a link to it in the email. For small email lists a public dropbox works fine. This also keeps the email size down.
Using Base64 to embed images in html is awesome. Nonetheless, please notice that base64 strings can make your email size big.
Therefore,
1) If you have many images, uploading your images to a server and loading those images from the server can make your email size smaller. (You can get a lot of free services via Google)
2) If there are just a few images in your mail, using base64 strings is definitely an awesome option.
Besides the choices provided by existing answers, you can also use a command to generate a base64 string on linux:
base64 test.jpg
For those who couldnt get one of these solutions working:
Send inline image in email
Following the steps laid out in the solution offered by #T30 i was able to get my inline image to display without being blocked by outlook (previous methods it was blocked). If you are using exchange like we are then also when doing:
service = new ExchangeService(ExchangeVersion);
service.AutodiscoverUrl("email#domain.com");
SmtpClient smtp = new SmtpClient(service.Url.Host);
you will need to pass it your exchange service url host. Other than that following this solution should allow you to easily send embedded imgages.
It may be of interest that both Outlook and Outlook Express can generate these multipart image email formats, if you insert the image files using the Insert / Picture menu function.
Obviously the email type must be set to HTML (not plain text).
Any other method (e.g. drag/drop, or any command-line invocation) results in the image(s) being sent as an attachment.
If you then send such an email to yourself, you can see how it is formatted! :)
FWIW, I am looking for a standalone windows executable which does inline images from the command line mode, but there seem to be none. It's a path which many have gone up... One can do it with say Outlook Express, by passing it an appropriately formatted .eml file.
You need 3 boundaries for inline images to be fully compliant.
Everything goes inside the multipart/mixed.
Then use the multipart/related to contain your multipart/alternative and your image attachment headers.
Lastly, include your downloadable attachments inside the last boundary of multipart/mixed.
There's actually a very good blog post that lists pro's and cons of three different approaches to this problem by Martyn Davies. You can read it at https://sendgrid.com/blog/embedding-images-emails-facts/.
I'd like to add a fourth approach using CSS background images.
Add
<div id="myImage"></div>
to your e-mail body and a css class like:
#myImage {
background-image: url('data:image/png;base64,iVBOR...[some more encoding]...rkggg==');
width: [the-actual-image-width];
height: [the-actual-image-height];
}
The following is working code with two ways of achieving this:
using System;
using Outlook = Microsoft.Office.Interop.Outlook;
namespace ConsoleApp2
{
class Program
{
static void Main(string[] args)
{
Method1();
Method2();
}
public static void Method1()
{
Outlook.Application outlookApp = new Outlook.Application();
Outlook.MailItem mailItem = outlookApp.CreateItem(Outlook.OlItemType.olMailItem);
mailItem.Subject = "This is the subject";
mailItem.To = "john#example.com";
string imageSrc = "D:\\Temp\\test.jpg"; // Change path as needed
var attachments = mailItem.Attachments;
var attachment = attachments.Add(imageSrc);
attachment.PropertyAccessor.SetProperty("http://schemas.microsoft.com/mapi/proptag/0x370E001F", "image/jpeg");
attachment.PropertyAccessor.SetProperty("http://schemas.microsoft.com/mapi/proptag/0x3712001F", "myident"); // Image identifier found in the HTML code right after cid. Can be anything.
mailItem.PropertyAccessor.SetProperty("http://schemas.microsoft.com/mapi/id/{00062008-0000-0000-C000-000000000046}/8514000B", true);
// Set body format to HTML
mailItem.BodyFormat = Outlook.OlBodyFormat.olFormatHTML;
string msgHTMLBody = "<html><head></head><body>Hello,<br><br>This is a working example of embedding an image unsing C#:<br><br><img align=\"baseline\" border=\"1\" hspace=\"0\" src=\"cid:myident\" width=\"\" 600=\"\" hold=\" /> \"></img><br><br>Regards,<br>Tarik Hoshan</body></html>";
mailItem.HTMLBody = msgHTMLBody;
mailItem.Send();
}
public static void Method2()
{
// Create the Outlook application.
Outlook.Application outlookApp = new Outlook.Application();
Outlook.MailItem mailItem = (Outlook.MailItem)outlookApp.CreateItem(Outlook.OlItemType.olMailItem);
//Add an attachment.
String attachmentDisplayName = "MyAttachment";
// Attach the file to be embedded
string imageSrc = "D:\\Temp\\test.jpg"; // Change path as needed
Outlook.Attachment oAttach = mailItem.Attachments.Add(imageSrc, Outlook.OlAttachmentType.olByValue, null, attachmentDisplayName);
mailItem.Subject = "Sending an embedded image";
string imageContentid = "someimage.jpg"; // Content ID can be anything. It is referenced in the HTML body
oAttach.PropertyAccessor.SetProperty("http://schemas.microsoft.com/mapi/proptag/0x3712001E", imageContentid);
mailItem.HTMLBody = String.Format(
"<body>Hello,<br><br>This is an example of an embedded image:<br><br><img src=\"cid:{0}\"><br><br>Regards,<br>Tarik</body>",
imageContentid);
// Add recipient
Outlook.Recipient recipient = mailItem.Recipients.Add("john#example.com");
recipient.Resolve();
// Send.
mailItem.Send();
}
}
}
One additional hint to Pavel Perna's post which helped me very much (cannot comment with my reputation, that's why I post this as answer): In some versions of Microsoft Exchange, the inline contents disposition is removed (see this post by Microsoft). The image is simply not part in the mail the user sees in Outlook. As a workaround, use "Content-Disposition: attachement" instead. Outlook 2016 won't show images as attachement that are used in the mail message, although they use the "Content-Disposition: attachement".
Try to resolve that with Context.Request:
<img width="150" height="60" src="#($"{Context.Request.Scheme}://{Context.Request.Host}{Context.Request.PathBase}/images/logo.png")" />
In my situation, when I used Content-ID I had that image as an attachment as well, and that was not the best solution.

Sending Email with the right Encoding. (Outlook gibberish hebrew )

I'm sending an Hebrew email to two places, one is Gmail and the other is Outlook.
The problem:
Gmail is working fine every time (they detect the Encoding automatically) but Outlook display the body in gibberish, I can fix it if I change the display encoding from Hebrew(Windows) to Unicode(UTF-8) (when opening the message display in Outlook).
worth mention that the headers and the subject are fine.
The Question: How can I "tell" Outlook or any other program to view the mail with Unicode(UTF-8) encoding ? without the need to do it manually.
I try to set the encoding, char-set and what not but I can get it to work.
Code related:
public static void SendEmail(MailMessage msg )
{
ContentType mimeType = new System.Net.Mime.ContentType("text/html");
msg.AlternateViews.Add(System.Net.Mail.AlternateView.CreateAlternateViewFromString(msg.Body, mimeType));
SmtpClient smtp = new SmtpClient
{
Host = "mailgw.netvision.net.il",
Port = 25,
DeliveryMethod = SmtpDeliveryMethod.Network,
UseDefaultCredentials = false,
Credentials = new NetworkCredential(uName,uPass)
};
smtp.Send(msg);
}
Here is a couple examples how I tried to play with the Encoding:
msg.BodyEncoding = Encoding.ASCII;
msg.BodyEncoding = Encoding.UTF8;
msg.BodyTransferEncoding = TransferEncoding.SevenBit;
At the end what make it work is the configuration of the alternative view, like this:
AlternateView view = System.Net.Mail.AlternateView.CreateAlternateViewFromString(msg.Body, Encoding.UTF8, "text/html");
msg.AlternateViews.Add(view);
As you can see I've set the MIME (as I did before) but I also set the Encoding to UTF-8, what solve the problem.
Firstly, it would be a good idea to HTML encode all Unicode characters in the HTML body itself - https://en.wikipedia.org/wiki/Character_encodings_in_HTML.
Secondly, please port the complete MIME source of the message that you create.

Incorrect encoding in e-mails sent with System.Net.Mail.MailMessage

When receiving e-mails sent with System.Net.Mail.MailMessage some recipients seem to have encoding issues with the e-mail. For example charachter ä is displayed as ä. I have set encoding properties:
System.Net.Mail.MailMessage msg = new System.Net.Mail.MailMessage();
...
msg.BodyEncoding = System.Text.Encoding.UTF8;
msg.SubjectEncoding = System.Text.Encoding.UTF8;
What else can I do?
Update:
If I use the Body property the e-mail is displayed correctly, but when I use the AlternateViews property the e-mail is displayed incorrectly.
Complete code:
SmtpClient smtpClient = new SmtpClient("some.host.com");
MailMessage msg = new MailMessage();
msg.To.Add("someone#host.com");
msg.From = new MailAddress("name#host.com", "Name Name");
msg.Subject = "Test";
//Displays as ä
//msg.Body = "ä";
// Displays as ä
AlternateView htmlView = AlternateView.CreateAlternateViewFromString("ä", new ContentType(MediaTypeNames.Text.Html));
msg.AlternateViews.Add(htmlView);
smtpClient.Send(msg);
When sending to Gmail the e-mail is displayed correctly, but when sending to an Exchange server the e-mail is displayed incorrectly. I have tested in .NET 3.5 and 4.5.
Try adding the content type to the Alternative View:
AlternateView htmlView = AlternateView.CreateAlternateViewFromString("ä", new ContentType(MediaTypeNames.Text.Html));
htmlView.ContentType.CharSet = Encoding.UTF8.WebName;
I don't think the BodyEncoding and SubjectEncoding affects reading of messages in any way - it applies to when you send messages and sets the text encoding for the messages and headers when messages are sent.
SmtpClient will read the content-type and charset encoding from messages sent and decode the content of the message and subject according to the encoding it finds in the headers.
If your message is not getting decoded, it seems that the messages are possibly not encoded correctly (or potentially double encoded UTF-8 encoded string getting encoded again by a message encoder), the request headers on the message don't properly match the actual encoding of the message or a charset format that isn't supported in .NET is used.
The only way to know though is to look at the actual raw request trace of a message that fails to see what's actually getting sent.
You might want to set up System.NET tracing for email messages (see http://codepaste.net/j52ktp) or else monitor the TCP/IP stream with something like Wireshark to see what's actually going over the wire and what the headers are instructing the client to do with the data.
FWIW, there's no reason if a message is properly UTF-8 encoded for SmtpClient to not read these messages correctly.

MailSystem.NET subject encoding

I'm currently using MailSystem.NET SMTPClient to send email, the email content contains Chinese character in both Subject and Body. By the following code, I'm able to set the Email's body to be Encoded correctly, but Subject is still not Encoded and appeared as ???? in Received Email.
ActiveUp.Net.Mail.Message message = new ActiveUp.Net.Mail.Message();
....
message.Charset = "utf-8";
SmtpClient.Send(message, serverName);
Could anyone familiar with MailSystem.Net kindly tell me how to set the subject as encoded in utf-8 as well? Thanks.
I had a similar problem with Polish chars in my email subjects. Solved it this way (VB.NET):
message.Subject = "=?UTF-8?B?" &
Convert.ToBase64String(Encoding.UTF8.GetBytes(outboxMessage.Title)) &
"?="
Now everything works as expected.

Sending a mail as both HTML and Plain Text in .net

I'm sending mail from my C# Application, using the SmtpClient. Works great, but I have to decide if I want to send the mail as Plain Text or HTML. I wonder, is there a way to send both? I think that's called multipart.
I googled a bit, but most examples essentially did not use SmtpClient but composed the whole SMTP-Body themselves, which is a bit "scary", so I wonder if something is built in the .net Framework 3.0?
If not, is there any really well used/robust Third Party Library for sending e-Mails?
The MSDN Documentation seems to miss one thing though, I had to set the content type manually, but otherwise, it works like a charm :-)
MailMessage msg = new MailMessage(username, nu.email, subject, body);
msg.BodyEncoding = Encoding.UTF8;
msg.SubjectEncoding = Encoding.UTF8;
AlternateView htmlView = AlternateView.CreateAlternateViewFromString(htmlContent);
htmlView.ContentType = new System.Net.Mime.ContentType("text/html");
msg.AlternateViews.Add(htmlView);
What you want to do is use the AlternateViews property on the MailMessage
http://msdn.microsoft.com/en-us/library/system.net.mail.mailmessage.alternateviews.aspx
Just want to add that you can use defined constants MediaTypeNames.Text.Html and MediaTypeNames.Text.Plain instead of "text/html" and "text/plain", which is always a preferable way. It's in System.Net.Mime namespace.
So in the example above, it would be:
AlternateView htmlView = AlternateView.CreateAlternateViewFromString(htmlContent, null, MediaTypeNames.Text.Html);
I'm just going to put a note here for anyone that's having problems and finds their way to this page - sometimes, Outlook SMTP servers will reconvert outgoing email. If you're seeing your plain-text body vanish entirely, and nothing but base64-encoded attachments, it might be because your server is reencoding the email. Google's SMTP server does not reencode email - try sending through there and see what happens.
On top of using AlternateViews views to add both the html and the plain text view, make sure you are not also setting the body of the Mail Message object.
// do not do this:
var msg = new MailMessage(model.From, model.To);
msg.Body = compiledHtml;
As it will make your email contain the html content in both views, overriding the alternative views.
For the people(like me) who've had the problem of gmail displaying the plaintext part instead of the html part.
Gmail seems to always display the last part in your message.
So if you've added the html part before your plain text part chances are gmail will always show the plain text variant.
To fix this you can simply add the plain text part before your html part.
For anyone who bumped into this issue you might want to check if you have preheader tags in your html.
In my html I've added a tag with a phrase of "Activate your client admin account by clicking the link.".
It seems like gmail is flagging the phrase "clicking the link" after removing it, all my emails that has been sent, are going straight to the inbox.

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