All incoming smtp connections dropped immediately


New Member
Nov 30, 2019
Hi, Just installed PMG as a VM on a Hyper-V server to trial it out and have done what I think is all the basic configuration according to the tutorial on the forum but cannot get any incoming mail. When I use something like the Microsoft Connectivity Analyser to inject some mail it says failed, connection was established but no banner was received. Using MXToolbox says the connection was hung-up after the connection was established. My firewall is forwarding all port 25 traffic to the server IP ok but I don't seem to be able to get past this very first basic step in order to then check out other functions and the passing of mail on to my exchange server.
Is there a step I have missed somewhere to allow the PMG to accept connections or anything else I can do to try to diagnose exactly what is wrong. I am no Linux expert so am only using the GUI for configuration.
Any log in the Message Tracking center?
Nothing at all in the message centre, I suspect because nothing actually ever gets to properly connect so no messages are received
If you see no logs on the Mail Gateway, you have probably any issue in your firewall/network settings in your host/VM.?
I am able to connect over internal network to the PMG on port 8006 fine so the VM is available on the network ok. It also downloads AV updates etc so it can access internet. The firewall rule I was using to send port 25 to my exchange server has simply had its IP changed to the new IP of PMG.
Just did as you always do in times like this and rebooted the PMG, now getting mail in!!
Thanks anyway Tom.


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