SMTP and IMAP server library for .NET

Question

Does anyone know a good SMTP/IMAP server library for C#?

I only found some long abandoned projects.

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Only SERVER SIDE libraries, please no more posts about client libs.

Thanks, Fionn

Answer 1

I am working on a project where I need to receive a mail via SMTP on the local network (a legacy application is sending a mail for integration purposes). Originally, I was going to use the SMTP server in IIS and use event sinks but that seems a little heavy-handed. I am currently evaluating the following 3 candidate libraries:

nDumbster: Open source but not a fully-implemented server. Originally used for unit tests. It parses the mail to an object for easy inspection. I had to revise it to raise an event when a message was received.

SmtpServer: Modern design using .NET TPL and Implements STARTTLS. Source code does not seem readily available. Provides a few hooks when message is received but appears to hand you the message contents as a blob. (I didn't get to test this as it requires .net 4.5)

Rnwood.SmtpServer: Looks to be full-featured and source code is available although documentation is lacking.

Answer 2

LumiSoft.Net, a library from the LumiSoft mail server, is a free server side library. The server classes (e.g. IMAP Server, POP3 Server and SMTP Server) fire events when they need information or action for your server application, for example "give me a list of messages in virtual folder XXY".

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Answer 3

I've used DotNetOpenMail in the past.

Answer 4

You didn't mention whether you are looking for free or paid/commercial. I have used IPWorks from nsoftware with great success in the past.

Answer 5

For SMTP, there's System.Net.Mail. For IMAP, I don't know. But once you fetch the email from the server, you'll want to parse it. The MIME parsing is the hard part. For that, I use, and recommend, SharpMimeTools.