Twilio: Widespread Microsoft 365 IP Block Causing Delivery Failures for Multiple Users
Timeline of updates
- resolved
The incident is resolved and block rates are back to normal but customers will see change in block classifications from Microsoft 365. Users that continue to see elevated blocks can submit delisting requests to Microsoft by sending an email with a copy of the error message, and the blocked IP address, to "delist@microsoft.com". Delisting requests can also be made via the Office 365 Anti-Spam IP Delist Portal at https://sender.office.com/ (opens in new tab)
From Twilio’s published incident history: for incidents before Rewindex began polling this status page, only the final update text is available.
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This incident predates live tracking (October 17, 2026). It came from the vendor’s own published history, which is not covered by checkpoints.
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Cite this
Status incident (vendor impact label: none) posted by Twilio, started 2026-08-15 01:31 UTC, resolved after 34 min, 1 update(s).
- Title
- Widespread Microsoft 365 IP Block Causing Delivery Failures for Multiple Users
- Vendor
- Twilio
- Date
- URL
- https://rewindex.com/company/twilio/incidents/f8vsxj0hk5by
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