IMAP4 server for .NET

Question

Are there any free (non-GPL) libraries for .NET that provide IMAP4 server side functionality?

E.g. handles the socket level and message handshaking so that an IMAP4 client (such as outlook) can retrieve, read, edit and/or delete messages.

I am not trying to connect to an IMAP4 server, I'd like the assistance to implement one.

Answer 1

I'm not sure if you have tried Indy (previously a set of Delphi components) - although I am not sure if they do IMAP4 as their web page is a bit blank, as is their CodePlex hub. Go to their website. Other than that I'm not sure - even Google only shows clients.

Answer 2

I know I'm answering my own question, but after yet more searching I think I may have found something matching my needs:

NMail

Features

• NMail is a 100% .net application.
• A Windows installer and setup wizard.
• ASP.net Webmail.
• An ASP.net administration site.

IMAP Server Features

• Support for ACLs.
• NTLM authentication (Secure Password Authentication (SPA) under Outlook and Outlook Express).
• Support for SSL/TLS encryption.
• SASL plain authentication support (when using an encrypted session).

SMTP Server Features

• Support for SSL/TLS encryption.
• Flexible API for filtering and altering messages. E.g. To remove spam or to rewrite addresses, etc.

Answer 3

You can check Lumisoft Mail Server. The license is FREEWARE.

General:

* SMTP/POP3/IMAP4/WebMail
* IP access filtering
* User mailbox size limit
* Supports XML or MSSQL databases
* Nice GUI for administation
* Well commented source code included

SMTP:

* All basic smtp features
*  Supports multiple domains
*  Supports multiple e-address for one mailbox
*  Supports aliases(Mailing lists). Supports public and private 
   (needs authentication) lists.
*  Supports email routing. eg *ivar* pattern routes all addresses containing 
   ivar to specified mailbox or remote address
*  SMTP AUTH (LOGIN CRAM-MD5) (supported authentication types)
*  SMTP SIZE, PIPELINING, 8BITMIME, CHUNCKING support
*  SMTP custom message filters
*  Relay can be controlled by IP access or authentication

POP3:

* All basic pop3 features
* APOP command for secure authentication
* POP3 AUTH (LOGIN CRAM-MD5) (supported authentication types)
* POP3 remote accounts

WebMail (ASP.NET):

* Standalone webmail, can be used any with IMAP based mailserver
* Supports XML or MSSQL databases
* Multiple UI languages