4.4.7: delivery time expired

What it means

X.4.7 is used when a message is too old: it sat on a server longer than that server keeps trying, or longer than a time limit the sender set. It appears in two places. In a delay warning, 4.4.7 tells you the message is still queued. In the final bounce it explains why the queue gave up, and some servers keep the 4 class even then, because the failures behind it were temporary. RFC 3463 asks servers to report the actual problem met during delivery instead of this code when they can, so look in the bounce for the last error the server received.

Common causes

• The receiving server refused or deferred every attempt until the retry period ran out.
• The recipient domain's servers were unreachable for a long time.
• A delivery deadline set by the sender passed before the message was delivered.

How to fix it

1. 01Find the last error in the bounce or in the sending server's logs; that is the real reason.
2. 02Look up that error's code on its own page and fix that problem.
3. 03Check the recipient domain's MX records and whether its servers answer.
4. 04Resend the message once the cause is fixed; an expired message is not retried.

Sources

What this page rests on, checked on 20 Oct 2026. The explanation is ours; the reply text is the server's.

• RFC 3463, section 3.5: Network and Routing Statusrfc-editor.org
• IANA, SMTP Enhanced Status Codes registry (Enumerated Status Codes)iana.org

Further reading

• MX lookup