SMTPDummy

SMTPDummy is simple and practical, and responds to all SMTP commands in a positive manner. It does not require installation and is portable you can run it from a USB stick. If does not require configuration, simply run the executable and you have a SMTP server. Its purpose is to simply respond to SMTP commands without functioning as an SMTP server in any way. While it's running, you can see the server's log and the individual messages that it has received. Messages can be displayed as plain text or HTML. You can use SMTPDummy for debugging your software sending application or for development and integration environments.