An e-mail arrived late: finding where it waited, using the Received lines of the header

The short answer: every server an e-mail passes through writes a Received line into the header, with the date and time. Reading those lines from the bottom up and comparing the times shows where the message waited: on the sender's server, along the way, or already in your mailbox, waiting for your phone or program to fetch it. Each place has a different explanation and a different fix.

How to see the header

Where	How
Webmail	Open the message, go to the More menu and choose to view the source (or show the headers).
Classic Outlook	Open the message, File, Properties: the headers are in the box at the bottom.
Gmail	From the message menu, choose Show original.

What else the header tells you (SPF, DKIM, DMARC) is in reading an e-mail header.

Reading the Received lines

The line at the bottom is the first: the sender's server. The line at the top is the last: our server, delivering into your mailbox. A simplified example:

Received: by delivery-server (ours) ... 10:47
Received: from relay.example.net ... 10:46
Received: from senders-pc ... 09:12
Date: ... 09:11

Here the message was written at 09:11 and left the computer at 09:12, but only reached the next server at 10:46. The delay was on the sender's side. Check each line's time zone (+0200 or +0000, for example) before comparing times.

Where it waited, and what that means

Where the gap is	What it usually is
Between Date and the first Received	The message sat in the sender's outbox (no network, program closed), or their computer clock is wrong.
Between servers, along the way	A server refused temporarily and the sending server tried again later. Some servers deliberately hold back the first message from an unknown sender. See errors 421 and 451.
None: the top line has the right time, but you saw the message late	The message was already in your mailbox. The delay was the device: a POP program that only checks now and then, or a phone in battery saving. See how push e-mail works.

If the delay is always from the same sender, send them the header: they are the ones who can fix it. If it is from several senders and the gap is on our line, open a support ticket with the full header of one or two messages.

Do not trust only the time shown in the message list. Many programs show the Date, which is the sender's computer time. If that clock is wrong, the message looks late (or from the future) without having waited anywhere.

Messages often arriving late? Open a ticket with the full header of one of them.

Open a support ticket

Categories

Categories