Hello Everyone..
I'm new to the exchange world and was given a project to upgrade our exchange 2007 server to 2013 then eventually to 2016, but I've run into some issues.
I'm currently running Exch13 (CU20) in coexistence with 2007 on a windows server 2008 r2 (hyper-v), and both the CAS and MBX roles are on one server.
My issue is that when I try to receive mail on the new server using the default receive connectors with all IP ranges, the SMTP service on port 25 will hang. I can telnet to it for maybe a minute and still get the 220 banner, but then after a short time it stops receiving the banner. When I run a netstat on the server, I can see the connection is established but not dice on the banner, and the emails stop coming in. Also when I run netstat I only see the frontend transport service connecting to port 25.
The only way I can receive mail right now is to have a dedicated frontend connector to the 2007 server which is currently receiving all the mail and sending to mailboxes on 2013. Once I switch to the default frontend connector with all IP ranges, everything just stops. So it doesn't make sense that 1 IP address will keep the service up, but all of them suddenly brings things to a halt.
Any help would be appreciated, and apologies if I'm not making sense on my question.