In version 1.8.3 of DIdiSoft OpenPGP Library for .NET you will find a full featured PGP/MIME support. The weird thing is that it is designed to be a plugable API for easy integration with third party Mail Libraries for .NET.
The solution in brief
The PGP/MIME support is located in a new class PGPMailLib located in the namespace DidiSoft.Pgp.Mail in additional DLL DidiSoft.Pgp.Mail.dll.
Why not your own solution instead of plugable API?
A decent nowadays Email library must provide a good Email MIME (Multipurpose Internet Mail Extensions) parser and implementation of the network communication (Mail Send/Receive – POP3/IMAP, SMTP protocols). We can judge the complexity of those tasks by observing the implementation of the System.Net.Mail namespace in the .NET Framework – its MIME parser supports only a limited set of the MIME standard and this is the main reason why so many third party Mail APIs for .NET exist !
Which third party Mail Libraries are supported ?
Every library with a good MIME parser will integrate fine with DidiSoft.Pgp.Mail.dll. We have tested so far with Aspose.Email, Rebex.Mail, OpenPop and MimeKit. Even an Outlook plugin was created during the beta testing period from one of our clients who needed this functionality at that moment, when it was still under development.
Where to get more information
You can continue from here to the tutorial chapter dedicated to the PGP/MIME support for .NET.