When setting up a process to deliver emails from BizTalk, treat I always configure the SMTP information correctly, I always (this has happened to me four times now) start testing it and it is continually failing. The following error is as follows:
The message could not be sent to the SMTP server. The transport error code was 0x80040217. The server response was not available.
The resolution is that I had forgotten to configure the Send Handler with the smtp server address. Even though the documentation states that the configuration is overridden in the send port configuration, you still need to set up the address initially.