Hi!
I have an issue with some reporting software sending bulk emails after our Exchange 2013 migration.
I can see the connections in the firewall and I can see the first connections under the protocol logs in the Exchange servers. What happens is that after ~10 emails, within the same amount of seconds from what I can tell, the mail flow just stops to the Exchange server. I cant seem to find an error message anywhere within the Exchange logs and I've tried updating the receive connector with higher timeouts / Connection limits but the users still cant send all the invoices etc right away.
We have multiple applications / receive connectors with this issue and the users did not report any issues with Exchange 2010 so I am assuming that this issue did not exist there.
We're running two multi-role (CAS/MB) Exchange 2013 servers in a DAG. Exchange 2010 is not fully decommissioned yet but all links and users are moved to 2013.
Any help is much appreciated!