When SMTP credentials expire, a relay starts rejecting recipients or the mail server goes down, Odoo does not complain: it quietly parks every message in the outgoing queue in Delivery Failed state. Nobody notices until a customer asks why the invoice never arrived — often days later. This module watches the queue and emails your administrators a summary of what is failing: subjects, recipients and the first error the mail server returned. Free and open source (LGPL-3), Odoo 14.0 through 19.0.

• Works on install — enabled by default: 5 stuck messages, older than 60 minutes, checked every 4 hours.
• Actionable summary — the 20 oldest stuck messages with subject, recipient and the exact SMTP error.
• Force-sent, never queued — the alert is delivered in-process, because the mail queue is exactly what is broken.
• No inbox flood — at most one alert every 24 hours, however long the outage lasts.
• Per-installation switch — one checkbox in General Settings, plus a configurable threshold and age window.
• Never feeds itself — alert messages are flagged and are never counted as evidence of a broken queue.

Screenshots

One switch in Settings → General Settings, with the alert threshold and the age window below it.

The alert administrators receive: how many messages are stuck, and for each one the subject, the recipient and the error returned by the mail server.

The queue the alert is about — Settings → Technical → Email → Emails. Without this module nothing tells you it looks like this.

Installation

1. Open Apps, remove the default "Apps" filter if needed, and search for Failed Email Alerts.
2. Click Install. Only standard modules (base_setup, mail) are required — watching starts immediately.

Configuration

1. Open Settings → General Settings and scroll to the Emails section (called Discuss on Odoo 14.0 – 17.0).
2. Failed Email Alerts is on by default; untick it to silence the watchdog on this database.
3. Alert Above (emails) — how many stuck messages are needed before an alert goes out (default 5, floor 1).
4. Minimum Age (minutes) — messages queued more recently than this are normal traffic and are not counted (default 60, floor 5).
5. Make sure every administrator who should be warned has an email address on their user record.

Usage

1. The scheduled action "Email: alert on a stuck outgoing queue" runs every 4 hours and counts messages in Outgoing or Delivery Failed state older than the age window.
2. Above the threshold, every user with Settings access and an email address receives one summary of the 20 oldest stuck messages.
3. A further alert is not sent for another 24 hours, so a broken relay cannot turn into an inbox flood.
4. Open Settings → Technical → Email → Emails to inspect and retry the queue once the mail server is fixed.

Version notes

Identical behavior on every supported series (14.0 – 19.0); only the settings-view markup and the ir.cron fields differ internally.

License: LGPL-3 · Source on GitHub · Issues and contributions welcome.