First, I will thank you for your help in the last weeks! It was a pleasure for me getting so much feedback.
As you know already I am on developing a SMTP server in C#. Now, the current release is running very good and I want to do more stress test on it. Therefore it would be nice if you have time to add me to your newsletter or to send me emails to the address email@example.com . The SMTP server has implemented different events like OnClientConnect, OnRecipientAccept, OnHasAttachment, OnUsedHtmlMessage,... to implement your own handler for allowing attachments, or using a antivirus product.
The current release as a web frontend to change properties and add a new email address. My POP3 server is not yet using the new SQL storage, but there is a simple webmailer for it.
Thank you for your testing! In 2-3 weeks I will put the interface to a demo server where you can add your domain or create a account for one of my test domains.
Note: The SMTP server does not allow sending emails to other domains!