While trying out an example in Biztalk 2006 R2, I got into following error
The adapter failed to transmit message going to send port "BTDemoFlatFileSendPort" with URL "kamlesh.panchal@conchango.com". It will be retransmitted after the retry interval specified for this Send Port. Details:"The server rejected one or more recipient addresses. The server response was: 550 5.7.1 Unable to relay for x.y@mangosoftware.com".
and having spent couple of hours debugging through errors and warnings in Health & Activity Tracking as well as following
- Configuring virtual SMTP server using IIS,
- Configuring relay restrictions
I thought of posting this up here for us BBs (Biztalk Beginners)
How to enable SMTP services on IIS server?
Click Start -> Control Panel -> Add or Remove Programs
Click <Add/Remove Windows Components> from the left tool bar.

Select <Internet Information Services (IIS)>
Now Click <Details> button

Select <SMTP Serrvice>
Press OK button.
How to configure Default Virtual SMTP Server on IIS?
Fire up IIS
Rename <Default SMTP Virtual Server> to say mySMTP
Right click on <mySMTP> -> Properties

Pull the IP address of your local machine under <IP address>
Click on <Advanced> button to ensure port 25 is assigned to this IP.

Click on tab <Access>
Click button <Relay…>

Add your IP in the list.
Note: Until you have granted access to your local machine/IP running an application on the same machine and trying to route a mail would throw error as mentioned earlier. (SMTP error 550)
How to configure your SMTP adapter? (in Biztalk)
Open up <BizTalk Server 2006 Administrator Console>
Under your <BizTalk Group>, Click Platform Settings -> Adapters -> SMTP

Select appropriate host application under <Host name>
Click <Properties> button
Use your machine name as SMTP Server name
Plug your mail address against <From (e-mail address)>
Leave <Authentication type> as [Process account(NTLM)]
Remember to restart host application listed under <Host Instances>
Your <Send Port> configured (similar to below> should roll…

Where to find the warning and error logs when running Biztalk samples?
Ø Health and Activity Tracking and running queries on it.
Ø System Event Viewer / Log
References:
SMTP Server Setup
http://www.microsoft.com/technet/prodtechnol/WindowsServer2003/Library/IIS/e4cf06f5-9a36-474b-ba78-3f287a2b88f2.mspx?mfr=true
The server response was: 550 5.7.1 Unable to relay …
http://www.dotnet247.com/247reference/msgs/12/63761.aspx
Biztalk SMTP adapter example
http://www.apress.com/book/view/1590598490
