Outbound mail stopped

synertekcs

Title is incorrect, should say Inbound mail stopped… don’t see how to edit…

How to troubleshoot this when inbound mail suddenly stops?

All my domains have stopped receiving mail. I am able to login via the SoGo and send outbound mail from any user. Server provider has confirmed that inbound ports are not being blocked. When I do a message trace from my outbound test from a M365 mailbox it just says:

Office 365 received the message that you specified, but delivery to the recipient (‎###@####nexus.org‎) has been delayed. We’re working on delivering it.

This is the last record we have for the message: In process

Maybe something in logs somewhere?

synertekcs

Finally got an NDR.

Diagnostic information for administrators:

Generating server: BYAPR04MB5816.namprd04.prod.outlook.com
Receiving server: BYAPR04MB5816.namprd04.prod.outlook.com
####@####nexus.org
8/25/2022 10:46:42 PM - Server at BYAPR04MB5816.namprd04.prod.outlook.com returned ‘550 5.4.316 Message expired, connection refused(Socket error code 10061)’
8/25/2022 10:35:48 PM - Server at ####nexus.org (2606:4700:3031::6815:2e97) returned ‘450 4.4.316 Connection refused [Message=Socket error code 10061] [LastAttemptedServerName=####nexus.org] [LastAttemptedIP=2606:4700:3031::6815:2e97:25] [DM6NAM10FT025.eop-nam10.prod.protection.outlook.com](Socket error code 10061)’

synertekcs

So not sure why all of a sudden I’m getting connection refused.

synertekcs

Fixed the issue!

I had moved my domain to cloudflare. When the DNS records were recreated it set the A records to my mailcow server as proxied. Once I changed this to DNS only everything worked again.