# Twilio: Widespread Microsoft 365 IP Block Causing Delivery Failures for Multiple Users

> Twilio status incident “Widespread Microsoft 365 IP Block Causing Delivery Failures for Multiple Users” on 2026-08-15: impact none (vendor’s label), 34 min, 1 update(s). Archived by Rewindex.

Canonical: https://rewindex.com/company/twilio/incidents/f8vsxj0hk5by
Last updated: 2026-08-15T02:05:00Z

- Impact (vendor’s label): none
- Status: resolved
- Started: 2026-08-15 01:31 UTC · Resolved: 2026-08-15 02:05 UTC · Duration: 34 min
- Updates: 1
- [Vendor status page: https://status.twilio.com/incidents/f8vsxj0hk5by](https://status.twilio.com/incidents/f8vsxj0hk5by)
- [Company: Twilio](https://rewindex.com/company/twilio.md)

## Timeline of updates

- **resolved** 2026-08-15 02:05 UTC: 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/

_From the vendor’s published history: only the final update text is available for incidents before Rewindex began polling this page._

## 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).

- Canonical URL: https://rewindex.com/company/twilio/incidents/f8vsxj0hk5by
- Citation: Twilio, “Widespread Microsoft 365 IP Block Causing Delivery Failures for Multiple Users” (2026-08-15 01:31 UTC). Archived by Rewindex: https://rewindex.com/company/twilio/incidents/f8vsxj0hk5by (CC BY 4.0).
- Markdown link: `[Twilio: Widespread Microsoft 365 IP Block Causing Delivery Failures for Multiple Users (2026-08-15)](https://rewindex.com/company/twilio/incidents/f8vsxj0hk5by)`


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Canonical: https://rewindex.com/company/twilio/incidents/f8vsxj0hk5by · Markdown: https://rewindex.com/company/twilio/incidents/f8vsxj0hk5by.md · JSON: https://rewindex.com/api/v1/companies/twilio/incidents/f8vsxj0hk5by · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-11-04T14:20:27.664Z