39
MailSystem.NET contains all your need for IMAP4. It's free & open source.
(I'm involved in the project)
LumiSoft.ee - works great, fairly easy. Compiles with .NET 4.0.
Here are the required links to their lib and examples. Downloads Main:
http://www.lumisoft.ee/lsWWW/Download/Downloads/
Code Examples:
are located here: ...lsWWW/Download/Downloads/Examples/
.NET:
are located here: ...lsWWW/Download/Downloads/Net/
I am putting a SIMPLE sample up using their lib on codeplex (IMAPClientLumiSoft.codeplex.com). You must get their libraries directly from their site. I am not including them because I don't maintain their code nor do I have any rights to the code. Go to the links above and download it directly. I set LumiSoft project properties in my VS2010 to build all of it in .NET 4.0 which it did with no errors. Their samples are fairly complex and maybe even overly tight coding when just an example. Although I expect that these are aimed at advanced level developers in general.
Their project worked with minor tweaks. The tweaks: Their IMAP Client Winform example is set in the project properties as "Release" which prevents VS from breaking on debug points. You must use the solution "Configuration Manager" to set the project to "Active(Debug)" for breakpoints to work. Their examples use anonymous methods for event handlers which is great tight coding... not real good as a teaching tool. My project uses "named" event method handlers so you can set breakpoints inside the handlers. However theirs is an excellent way to handle inline code. They might have used the newer Lambda methods available since .NET 3.0 but did not and I didn't try to convert them.
From their samples I simplified the IMAP client to bare minimum.