Twilio: Elevated Microsoft 365 IP Blocks Causing Delivery Failures for Multiple Users
Timeline of updates
- resolved
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/ (opens in new tab) Users that are experiencing blocks at Microsoft Outlook Consumer domains can open a remediation request at http://olcsupport.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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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).
- Title
- Elevated Microsoft 365 IP Blocks Causing Delivery Failures for Multiple Users
- Vendor
- Twilio
- Date
- URL
- https://rewindex.com/company/twilio/incidents/r2gvsly2y5ty
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