Exchange 2013 not always delivering internal mail

[dayzd]

I've had a couple of reports of internal mail not being received, even though the sender's accounts show the message has been sent - it isn't hidden in an Outbox, neither is an error message bounced back to the sender. I've been investigating a particular example and used the Exchange Control Center's message tracking tool to see if I can find what is going on.

 

From the Sender's point of view, there are three messages - their initial message, the recipient's response, and their reply after that.

From the recipient's point of view, there are two messages - the sender's initial message, and their response, then nothing more.

 

The Sender is using OWA and the recipient is using Outlook 2013 in online mode.

 

Both EAC's Message Tracking tool and the 'Get-MessageTrackingLog' cmdlet do not show anything for the third message in the conversation (that was not received), but the message itself is sat in the 'Sent Items' folder of the sender, as if it sent normally.

 

 

 

Has anyone encountered this before?

[psydii]

If you don't get someone who has seen this behaviour before giving you some pointers beyond your own efforts, I recommend opening a paid support call with Microsoft. e-mail is a service that everybody expects to work, and when it doesn't, it has a disproportionate affect upon your userbase's opinion of the competency of the IT Team.

 

200+VAT is well worth it for nailing this sort of problem quickly.

 

Meanwhile, are you on the latest CU both client and server? Do you run any antivirus software that might be getting in the way?

[dayzd]

We're on CU8, since I hadn't spotted CU9 (honestly, I'm not on it with updates...). We use Sophos system-wide, but none of the mail features are enabled.

 

I think raising a support call may be worth it. If my support company can't figure it out themselves (I didn't commission this server personally), I think I'll end up doing that: you're right, it's a service that needs to work reliably. :-)

[Snuffkins]

I've seen issues with internal mail previously if an external DNS entry exists on the servers network adaptor. Probably isn't that, but it's something that you can check very quickly that can cause an intermittent issue like that. Although, you would normally see the messages stuck in the queue viewer with a DNS related error when that is the problem.