Uggghhhh! Even myself, the author of the Chilkat email component has been burned by this mistake more than once. When sending email, always always always remember to set the SmtpHost property. If you don’t, it defaults to the localhost. If you have IIS’s SMTP running on your computer, and it’s never been setup (or it’s not setup correctly), the SendEmail method still works fine because it hands the email to the localhost SMTP server. But that’s as far as it goes, because it just sits in the queue (i.e. the maildrop directory and then gets moved to the "badmail" directory) Meanwhile, you’re left waiting for your test email to arrive so you can check it — and it never does. You thought it was talking to your intended SMTP server, but it was not. If you check the Mailman.LastErrorText you’ll see the "Connecting to SMTP server localhost:25″ in your log, and if you check your source you’ll notice that the SmtpHost property was never set. Mystery solved…