Ah, thanks for the log. The problem is that you are connecting to POP3 server with Rebex IMAP client. These are two different protocols, so in order to connect to POP3 server, you'll need to connect via our Pop3 client. Try this code:
// create POP3 client instance
using (var pop3 = new Rebex.Net.Pop3())
{
// connect to Exchange POP3 server
pop3.Connect("exchange");
// authenticate
pop3.Login(username, password);
// get message list
Pop3MessageCollection list = pop3.GetMessageList();
// print some info
Console.WriteLine("{0} email(s) found.", list.Count);
// download all messages
foreach (Pop3MessageInfo info in list)
{
MailMessage mail = pop3.GetMailMessage(info.SequenceNumber);
// do something with the mail
// ...
}
// disconnect (required to commit delete operations)
pop3.Disconnect();
}
See more info at http://www.rebex.net/secure-mail.net/features/pop3.aspx
Moreover, I see that your company owns a license for IMAP component (it was sold separately until 2013). Since then we do not sell it separately, instead we sell the whole Rebex Secure Mail that contains all the mail protocols - IMAP, POP3, SMTP, EWS. For you as an owner of the IMAP component, there is 15% discount on upgrading to Rebex Secure Mail from your old license. See more info at http://blog.rebex.net/mail-and-terminal-emulation-product-list-simplified/