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none✓ Resolved

Microsoft Incident Resulting in Delivery Issues to M365

Mailgun•Fri, Sep 4, 2026, 12:20 PM
Status
resolved
Duration
34 minutes
Updates
2
Coverage
0 articles

INCIDENT TIMELINE

✓ ResolvedFri, Sep 4, 2026, 12:55 PM
This incident has been resolved.
monitoringFri, Sep 4, 2026, 12:22 PM
We are continuing to monitor for any further issues.
monitoringFri, Sep 4, 2026, 12:20 PM
Starting around 08:00 UTC, Microsoft began experiencing an incident causing an increased volume of deferred emails across all M365 regions. The affected responses are returning "451 4.7.500 Server busy". Our teams are actively monitoring the situation. No other email providers are currently affected.

📊 TECHNICAL DETAILS

Internal ID
707bac52-b850-40be-9bf1-281d7e702b58
External ID
cmp9x9s5n00g
🕐 Started
Fri, Sep 4, 2026, 12:20 PM
🔄 Last Updated
Fri, Sep 4, 2026, 12:55 PM
✓ Resolved
Fri, Sep 4, 2026, 12:55 PM
NONE
Impact Level
34 minutes
Total Duration
2
Status Updates
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