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

> Scaleway Transactional Email has degraded email delivery to Microsoft consumer domains such as Outlook and Hotmail. All sending pools are affected. Scaleway reports the state as identified. Delivery can take up to 1 hour. The cause is external, and Scaleway monitors MX timeouts.

- Provider: [Scaleway](https://outages.live/scaleway.md)
- Type: Incident
- State: identified
- Worst impact: Degraded performance
- Started: 2026-11-12 20:07 UTC
- Components: Transactional Email, Elements - Products - Transactional Email
- Official update: https://stspg.io/vktcg2t6rw3q

## Updates from Scaleway

### identified, 2026-11-12 20:42 UTC

Start: 2026-11-12 ~18:45 UTC (19:45 CET) Impact: Some emails can take up 1 hour to be delivered. Cause: External. Microsoft 365 / Exchange Online outage Mitigation: Continuous monitoring of MX timeouts

### identified, 2026-11-12 20:09 UTC

- 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,