Hi Folks, I have an odd problem. I have a Mailfoundry spam appliance that is used through a connector for all outgoing email. This smtp connector has been working fine for quite some time, however recently I have a problem where when I reply to an email from a certain domain (only this domain) Exchange bypasses the connector and sends the email directly causing a bounce due to invalid ptr. If I send an original email to this address it works just fine and routes mail through the connector to the appliance. But as soon as I reply it tries to send directly. I'm very confused as to why this may be happening and would love any suggestions!

I'm assuming that since you mentioned SMTP Connector that you are using Exchange Server 2000/2003. How many Exchange servers are in your environment? Jim McBee - Blog - http://mostlyexchange.blogspot.com

Hi Jim,It's Exchange 2003, there's only the one server. There are three connectors, one to go to my appliance set to run always, and two that were setup for testing by someone previous that are set to run never.

Hi Frank, From your description, I understand when you attempt to reply messages from a domain, the message flow bypass the SMTP connector and deliver to remote mail server directly. If you send a new message to the problem domain, the issue does not occur. If I am off base, please let me know. At this time, I suggest you remove the test SMTP Connectors and restart the Microsoft Exchange Routing Engine service to check whether the issue persists. If the issue persists, please use WinRoute to check whether only one SMTP connector is configured on the Exchange Organization: WinRoute Explained http://technet.microsoft.com/en-us/library/aa996165(EXCHG.65).aspx Download Link: http://www.microsoft.com/downloads/details.aspx?familyid=c5a8afbf-a4da-45e0-adea-6d44eb6c257b In addition, please also let me know whether the issue can be reproduced if you reply the message by using OWA. Mike

Hi Mike, Thanks for the suggestions. The problem mysteriously disappeared before I got a chance to look into it further. If I can reproduce the error I'll post back!