MailBee.NET SMTP enables .NET applications to compose, mail merge, and send mails to SMTP server or directly to recipients (via DNS MX Lookup). TLS/SSL, HTML mails with embedded images, ESMTP, send a web page, send with a single line of code, send to IIS SMTP queue, read and delivery receipt, secure authentication (NTLM, etc), international charsets, attachments, custom headers, XML, streams, multi-threading, and more. Royalty-free distribution.