# Scaleway: Incident silently edited: [Transactional Email] - world - Delayed email delivery to Microsoft domains (Outlook/Hotmail)

> Incident silently edited: [Transactional Email] - world - Delayed email delivery to Microsoft domains (Outlook/Hotmail). Detected 2026-11-12 by Rewindex: what changed on Scaleway’s status page, with the before/after diff.

Canonical: https://rewindex.com/change/rc8d102183e9816
Last updated: 2026-11-12T20:43:37Z

**Summary:** _summary pending_
- Kind: Silent edit · Label: not classified yet
- Changed: 2026-11-12 20:43 UTC · Detected: 2026-11-12 20:43 UTC
- [Source: https://status.scaleway.com/incidents/vyc7z0zdp42y](https://status.scaleway.com/incidents/vyc7z0zdp42y)
- [Company: Scaleway](https://rewindex.com/company/scaleway.md)
- Versions: before incident\_version:702/vyc7z0zdp42y@7ba08289838d → after incident\_version:702/vyc7z0zdp42y@73165af1613d
- Change 1 of 1 for this incident

Incident page (full timeline): [\[Transactional Email\] - world - Delayed email delivery to Microsoft domains (Outlook/Hotmail)](https://rewindex.com/company/scaleway/incidents/vyc7z0zdp42y.md)
## What changed

**1. Changed: Update** (identified) · 2026-11-12 20:07 UTC

```diff
  …Start: 2026-11-12 ~18:45 UTC (19:45 CET)
- - Impact: Email delivery to Microsoft consumer domains significantly delayed. Backlog of ~2,500 emails pending (incl. short-TTL OTP/auth messages at risk of expiry drops). All sending pools affected; partial delivery continues (8/min vs 25–30/min nominal). - Symptoms / findings: TCP connection timeouts (SYN unanswered) to Microsoft MX endpoints (52.101.x.x), spread across 10+ sending IPs and all pools. No connection refusals, no SMTP-level throttling — behavior consistent with a Microsoft-side infrastructure degradation, not reputation filtering. Deferrals peaked at ~1,000 MX-unavailable events / 10 min. No other destination domains affected beyond Microsoft consumer properties (+ unrelated, pre-existing Proximus/gtm-tc2 slowness tracked separately). - External cause: Microsoft 365 / Exchange Online outage, tracked by Microsoft as EX1550543 — acknowledged ~19:37 UTC, fix deployed ~18:30 CET, gradual recovery in progress. Refs: @MSFT365Status, Downdetector (outlook, microsoft-365). - Mitigation: None applicable (external provider). Emails retry automatically (1-min per-pool MX failure cache + per-email backoff); backlog expected to drain on Microsoft recovery. - Next steps: Continuo …
+ Impact: Some emails can take up 1 hour to be delivered. Cause: External. Microsoft 365 / Exchange Online outage Mitigation: Continuous monitoring of MX timeouts
```

## History of this incident

| When (UTC) | Change | Label |
| --- | --- | --- |
| 2026-11-12 20:43 UTC | Incident silently edited: \[Transactional Email\] - world - Delayed email delivery to Microsoft domains (Outlook/Hotmail) (this change) |  |

All Scaleway changes: [timeline](https://rewindex.com/company/scaleway/changes.md)
_Diff excerpts are shown on normalized text: dates, counters and tokens appear as ‹date›, ‹count›, ‹tok›; noise-only edits are hidden. Rewindex shows the changed passages, not a copy of the page._

## Cite this

Incident silently edited: [Transactional Email] - world - Delayed email delivery to Microsoft domains (Outlook/Hotmail) on Scaleway’s status page, changed 2026-11-12 20:43 UTC (change 1 of 1).

- Canonical URL: https://rewindex.com/change/rc8d102183e9816
- Citation: Scaleway, “Incident silently edited: [Transactional Email] - world - Delayed email delivery to Microsoft domains (Outlook/Hotmail)” (2026-11-12 20:43 UTC). Archived by Rewindex: https://rewindex.com/change/rc8d102183e9816 (CC BY 4.0).
- Markdown link: `[Scaleway: Incident silently edited: Transactional Email - world - Delayed email delivery to Microsoft domains (Outlook/Hotmail) (2026-11-12)](https://rewindex.com/change/rc8d102183e9816)`


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Canonical: https://rewindex.com/change/rc8d102183e9816 · Markdown: https://rewindex.com/change/rc8d102183e9816.md · JSON: https://rewindex.com/api/v1/changes/rc8d102183e9816 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-11-13T01:43:58.205Z