First of all I have read some of the material on this and I have seen some people suggesting to change the MaxAcknowledgementDelay on the Receive Connector to zero but some of those were in reference to coexistence with an Exchange 2003 server. I have also seen a suggestion stating that you could create a special receive connector for the particular domain and put all the IPs in it that send mail for that domain. I'm interested in getting some opinions on my particular situation.
I have a single Exchange 2010 server receiving email from the internet using a single "Internet Receive Connector". Usually I only see this in the SMTP Receive Log with spammers but occasionally it happens with legitimate email. Today it is happening with a new client and I would like to get it resolved. So the emails in question are never received by our users and the following is the end of the transmission in the Receive Log for one of the missing emails. Can anyone offer up some suggestions?
2015-02-11T20:22:46.477Z,EPTMAIL10\Internet Receive Connector,08D1C5ED19C2349D,27,LOCAL_IP:25, REMOTE_IP:45222,>,250 2.6.0 <!&!AAAAAAAAAAAYAAAAAAAAADcX//EdsDVGvdVvMvwfDP/CgAAAEAAAAGs9kWHPps5MrK7DOR3DVo8BAAAAAA==@REMOTEDOMAIN.ca> [InternalId=118165] Queued mail for delivery,
2015-02-11T20:22:46.499Z,EPTMAIL10\Internet Receive Connector,08D1C5ED19C2349D,28,LOCAL_IP:25, REMOTE_IP:45222,<,QUIT,
2015-02-11T20:22:46.499Z,EPTMAIL10\Internet Receive Connector,08D1C5ED19C2349D,29,LOCAL_IP:25, REMOTE_ip:45222,>,221 2.0.0 Service closing transmission channel,
2015-02-11T20:22:46.499Z,EPTMAIL10\Internet Receive Connector,08D1C5ED19C2349D,30,LOCAL_IP:25, REMOTE_IP:45222,-,,Local