Lost messages using SMTP this morning

I have two sites which were supposed to send out our critical daily reports today, and neither message arrived. Messages are normally sent out using Planner at 14:00:00.
This is what I see in the log:

Account: 120213-30
Ewons Affected: 272747 and 272748

Can you please send us a full backup with support files?

MOVED TO STAFF NOTE (240.5 KB)

Looks like the email was sent, but the Ewon received an error back from the mail server. Did you receive the retry email at 14:52?

I did receive that message at 14:53:27.
But, the log also reported a timeout on that message, didn’t it?
I didn’t think it came through, but must have made it on some subsequent retry.

I didn’t show a loss of connection… why didn’t the first e-mail go through?

It was an error from one of the mail servers which the message was routed through. It looks like the email was sent by the Ewon, but it received an error response. The only way to find out the exact reason would be to examine the logs from the mail servers involved. I don’t have access to those.