The DuoCircle Standard SMTP service provides a secure, authenticated outbound SMTP relay server. Unfortunately, it is inevitable that it may sometimes be abused for spamming. The information on this page should help any recipients of spam sent using DuoCircle Standard SMTP to report spam to stop future spam. Spam sent through our services is not be tolerated. Several headers are added to all messages sent via DuoCircle Standard SMTP to allow you and us to track abusers of the service. 


Those headers are:  

Header Name Description
X-Mail-Handler Always has a value of "DuoCircle Outbound SMTP", indicating that the message was processed by the DuoCircle Standard SMTP service.

X-Originating-IP The IP address of the connecting host sending this message, as determined from the TCP connection.
X-Report-Abuse-To Contains abuse reporting information, including a link to this page, and our abuse email address.
X-MHO-User An encrypted identifier used to determine the user responsible for sending the message. It is very important to include this header in any abuse reports.

Abuse reports should include the full headers and body of the message received. We prefer if you do not munge the receiving address. We do not provide complaints on to our customers except in aggregate form. Customers are not allowed to "listwash".

We thank you for your assistance in reporting any spam you receive from DuoCircle Standard SMTP customers. Together, we can work to keep the Internet clean.