How to Automate Sending Emails through Outlook interop using C#
I was tasked with a tricky issue in sending emails. Due to security concerns, the client’s IT team was not willing to share SMTP information for their mail settings and was only willing to set up an account in Outlook directly on a dedicated machine without sharing the password with us to send the emails. The client’s ask was to send emails through Outlook without letting users see the emails or Outlook itself.
Installing Office Interop for Outlook
Sending emails through Outlook can be done using Microsoft.Office.Interop.Outlook but the documentation is really lacking. If you need to do the same, I hope this will save you the hours of time it took me to figure out what ends up not being complex code.
Create a new desktop application project in Visual Studio. Install the Microsoft Office Interop for Outlook. I used the NuGet package manager to install it since it wasn’t present on my system:
Install-Package Microsoft.Office.Interop.Outlook
Automating E-mails using C#
I created a static class to send the email through Outlook. Note that my error handling code was replaced with Debug.Writeline. Remember to modify it to handle errors or implement logging so it doesn’t fail silently.
Email.cs:
using System;
using System.Diagnostics;
using System.IO;
using System.Runtime.InteropServices;
using Microsoft.Office.Interop.Outlook;
using Exception = System.Exception;
namespace Email.classes
{
public class Email
{
public static void SendWithEmbeddedImages(string to, string subject, string htmlMessage)
{
var missing = Type.Missing;
Application oOutlook = null;
NameSpace oNS = null;
Folder oCtFolder = null;
Items oCts = null;
MailItem msg = null;
var sHeaderPath = Path.Combine(Environment.CurrentDirectory, "emails", "header.jpg");
var sLogoPath = Path.Combine(Environment.CurrentDirectory, "emails", "logo.jpg");
try
{
// Create an Outlook application.
oOutlook = new Application();
// Get the namespace.
oNS = oOutlook.GetNamespace("MAPI");
//Assumes MAPI profile name is Outlook
oNS.Logon("Outlook", missing, false, true);
msg = (MailItem) oOutlook.CreateItem(OlItemType.olMailItem);
var attachHeader = msg.Attachments.Add(sHeaderPath, OlAttachmentType.olEmbeddeditem);
var attachLogo = msg.Attachments.Add(sLogoPath, OlAttachmentType.olEmbeddeditem);
attachLogo.PropertyAccessor.SetProperty("http://schemas.microsoft.com/mapi/proptag/0x3712001E", "logo");
attachHeader.PropertyAccessor.SetProperty("http://schemas.microsoft.com/mapi/proptag/0x3712001E",
"header");
msg.Subject = subject;
msg.To = to;
msg.BodyFormat = OlBodyFormat.olFormatHTML;
msg.HTMLBody = htmlMessage;
//Show email
msg.Display();
//Send email
//((Outlook._MailItem)msg).Send();
oNS.Logoff();
}
catch (Exception ex)
{
Debug.WriteLine("Automate Outlook throws the error: {0}", ex.Message);
}
finally
{
// Manually clean up the explicit unmanaged Outlook COM resources by
// calling Marshal.FinalReleaseComObject on all accessor objects.
// See http://support.microsoft.com/kb/317109.
if (msg != null)
{
Marshal.FinalReleaseComObject(msg);
msg = null;
}
if (oCts != null)
{
Marshal.FinalReleaseComObject(oCts);
oCts = null;
}
if (oCtFolder != null)
{
Marshal.FinalReleaseComObject(oCtFolder);
oCtFolder = null;
}
if (oNS != null)
{
Marshal.FinalReleaseComObject(oNS);
oNS = null;
}
if (oOutlook != null)
{
Marshal.FinalReleaseComObject(oOutlook);
oOutlook = null;
}
}
}
}
}
Example on how to call the class:
var sEmailPath = Path.Combine(Environment.CurrentDirectory, "emails", "single.html");
var htmlMessage = "";
if (File.Exists(sEmailPath))
{
//Load HTML from file
htmlMessage = File.ReadAllText(sEmailPath);
}
Email.SendWithEmbeddedImages("toaddress@test.com", "Outlook Automation Test", htmlMessage);
email.html:
<html lang="en" xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta charset="utf-8" />
</head>
<body>
<table width="600" border="0" align="center" cellpadding="0" cellspacing="0">
<tr>
<td><img src="cid:header"></td>
</tr>
<tr>
<td>
Hello world!
</td>
</tr>
<tr>
<td><img src="cid:logo"></td>
</tr>
</table>
</body>
</html>
Important Notes and Gotchas
- CIDs need to be unique. I’ve seen them on all other posts with the format “file.extension@{random #}” but keeping it simple like in the code above worked for me with no issues with Outlook 2016. I did not test on older versions of Outlook to confirm as I no longer have access to them.
- Outlook ignores font rules in the HTML/CSS you code in the email and defaults to Times New Roman. I know Outlook uses the Word renderer but I have no idea why and the only solution I found was to update the default font in Microsoft Word. Yes, to change the font in Outlook, you’ll need to update the default font in Word. Here’s how to set it:
- Open Word
Go to Options -> Advanced -> Web Options
Change the default font in the Fonts tab
- Open Word
- Outlook only supports a subset of HTML so don’t forget to test and verify everything as most CSS formatting won’t work in Outlook.
Regex to parse date formats when unknown
I’m working on an app that will parse different file sources and aggregate it for a report. Of course, each format has a different date format and trying to parse it all has proved to be a pain. I wrote a regex that’ll parse out just about every datetime format I’ve run into that I am sharing in case someone else finds it useful. I’ve put it on a Github gist along with a sample of the various dates I’ve tested it against and confirmed to work. If you find a format not covered by the regex, post a comment and I’ll update the gist.
Just a note that I haven’t finished parsing the timestamp (e.g. 1997-07-16T19:20:30+01:00) format. The date portion does get extracted correctly so I left it in.
Sitecore 8 Install Error: “The name you entered is not unique.”
I was working on my business partner’s computer to help him fix errors with his Sitecore instance for his certification class. He experienced multiple issues with the Sitecore 8 installer on Windows 8 and we went the manual route of deleting Sitecore to install clean and start from scratch. In the process, we:
- Deleted the IIS website instance in the IIS Manager
- Deleted the databases used by the instance
- Deleted the root folder in the filesystem
After launching the installer again, it kept returning the error “The name you entered is not unique.” when naming the Sitecore instance to one previously used. After checking the IIS metabase and a few other typical locations, couldn’t figure out where the Sitecore installer was finding the name since we deleted everything manually. It turns out that the Sitecore executable installer creates a registry entry under HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Sitecore CMS which is used to display information in Windows Programs and Features. This registry key is also checked during the installation process and if a child key with the same name as the one being installed is found, the above error message is shown.
To fix this:
- Start -> Run (or Windows Key + R)
- Type regedit
- Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Sitecore CMS.
- Delete the registry keys containing the information about the previously installed instance.
NOTE: You’ll need to relaunch the installer as it apparently caches the key information.
ASP.NET MVC Model Generator
In making the switch to ASP.NET MVC, I’ve moved away from using my old Data Access Layer that I’ve used for years and have opted to use Dapper as my ORM of choice in the quest for optimal performance. My DAL was actually pretty optimized for WinForms and WebForms (using straight SQL Queries and SQL parameters) but mapping it to models wasn’t something I had in mind when I created it. I’m finding Dapper takes some getting used too but it is still pretty fast. The downside is that writing the code for Models to wire it up is proving to be a little tedious.
To that effect, I wrote a little application that has helped me generate the models from a database dynamically. It’s in it’s infancy stages and something I cobbled together in less than 8 hours but it works. I’ll add more features too as time goes on if there’s enough interest or to satisfy my own needs. In the meantime, I’m open sourcing the project as it may help others and I’d love to see it become something grander if others are willing to contribute to it. There’s also some useful bits of code that others may find useful to reference like dynamically reading fields from a database, pluralization/singularization of words, amongst others.
You can find the repository on Github: https://github.com/gregvarghese/MVCModelGenerator