# Twilio: Elevated Microsoft 365 IP Blocks Causing Delivery Failures for Multiple Users

> Twilio status incident “Elevated Microsoft 365 IP Blocks Causing Delivery Failures for Multiple Users” on 2026-08-15: impact none (vendor’s label), 47 h, 1 update(s). Archived by Rewindex.

Canonical: https://rewindex.com/company/twilio/incidents/r2gvsly2y5ty
Last updated: 2026-08-17T13:30:00Z

- Impact (vendor’s label): none
- Status: resolved
- Started: 2026-08-15 14:16 UTC · Resolved: 2026-08-17 13:30 UTC · Duration: 47 h
- Updates: 1
- [Vendor status page: https://status.twilio.com/incidents/r2gvsly2y5ty](https://status.twilio.com/incidents/r2gvsly2y5ty)
- [Company: Twilio](https://rewindex.com/company/twilio.md)

## Timeline of updates

- **resolved** 2026-08-17 13:30 UTC: The incident is resolved as block rates at Microsoft 365 have returned to normal levels. Users that continue to see elevated blocks at Microsoft 365 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/ Users that are experiencing blocks at Microsoft Outlook Consumer domains can open a remediation request at http://olcsupport.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 14:16 UTC, resolved after 47 h, 1 update(s).

- Canonical URL: https://rewindex.com/company/twilio/incidents/r2gvsly2y5ty
- Citation: Twilio, “Elevated Microsoft 365 IP Blocks Causing Delivery Failures for Multiple Users” (2026-08-15 14:16 UTC). Archived by Rewindex: https://rewindex.com/company/twilio/incidents/r2gvsly2y5ty (CC BY 4.0).
- Markdown link: `[Twilio: Elevated Microsoft 365 IP Blocks Causing Delivery Failures for Multiple Users (2026-08-15)](https://rewindex.com/company/twilio/incidents/r2gvsly2y5ty)`


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Canonical: https://rewindex.com/company/twilio/incidents/r2gvsly2y5ty · Markdown: https://rewindex.com/company/twilio/incidents/r2gvsly2y5ty.md · JSON: https://rewindex.com/api/v1/companies/twilio/incidents/r2gvsly2y5ty · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-11-05T14:39:21.867Z