How to POP3 in C#

Using the new class is pretty easy.

static void Main(string[] args)
{
    try
    {
        Pop3 obj = new Pop3();
        obj.Connect("mail.xxx.com", "yyy", "zzz");
        ArrayList list = obj.List();
        foreach (Pop3Message msg in list )
        {
            Pop3Message msg2 = obj.Retrieve(msg);
            System.Console.WriteLine("Message {0}: {1}",
                msg2.number, msg2.message);
        }
        obj.Disconnect();
    }
    catch (Pop3Exception e )
    {
        System.Console.WriteLine(e.ToString());
    }
    catch (System.Exception e)
    {
        System.Console.WriteLine(e.ToString());
    }
}

Instantiate a new object, then call the List method. The List method will return an array of Pop3Message objects. You can then iterate through the Pop3Message objects and retrieve each in turn. Finally, you call the Disconnect method to release the socket. POP3 is described in RFC 1939. You can read the full specification from the IETF website.