My client is having intermittent problems sending email to a few customers. It has really only happened in the last five days and so far only to six different messages but they all have the same differences between a working and failed delivery.
In the screenshot below, the difference between a working and failed delivery is the Server IP/Hostname that it attempts to deliver to. I chose this recipient since their domain is generic. In other attempts with tens of messages per week it looks very similar.
For some reason Exchange Server obtains the IP for the domain of the recipient account instead of using the address from the MX record. (ie. mindspring.com instead of mx3.mindspring.com)
My client is running Small Business Server 2011 Standard w/ Exchange 2010. The rest of their ~200 messages a day send just fine.
My research so far:
For some reason Exchange Server obtains the IP for the domain of the recipient account instead of using the address from the MX record
- I don't understand that statement.