It's newly installed Exchange 2010 on Site C. Total there are four sites. Site A, Site B, Site C and Site D.
User can send email to users inside the organization and on the internet. The issue is User is not able to Receive Email from Internet and from all sites in the organization. After doing the Message Tracking, found that messages are getting stuck in the queue.
This is what I got in message tracking:
451 4.4.0 Primary target IP address responded with: 451 5.7.3 Cannot achieve Exchange Server authentication,” Attempted fadover to alternate host but that did not succeed. Either there are no alternate hosts
Checked the permissions on Receive Connector it was perfect all the permissions were intect. Deleted and Recreated the Bidirectional Routing Group Connector from Exchange 2010:
New-RoutingGroupConnector -Name "2010-2003" -SourceTransportServers "Exchange2010.corp.domain.com" -TargetTransportServers "Exchange2003.corp.domain.com" -Cost 1 -Bidirectional $truehttp://technet.microsoft.com/en-us/library/aa997292.aspx
After digging around all over the domain and sites I couldn't find anything which was blocking these mails.
But guess what happened, was doing some network activity and found that there is a CISCO ASA firewall between all the sites. It was CISCO, checked the firewall and found that SMTP Inspection is enabled. Disabled the SMTP Inspection and hoooooray.....Mails started flowing across the sites.
Cheers,
