Widespread Microsoft 365 IP Block Causing Delivery Failures for Multiple Users
Aug 15, 01:31 UTCAug 15, 02:05 UTC
Duration
34m
Impact
Informational
Root cause
Not disclosed
Twilio, 90 days
554 incidents
Affected
Not listed by the vendor.
Final update
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/
Timeline
- Resolved · Aug 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/
More from Twilio
Full history| Started | Incident | Impact | Duration |
|---|---|---|---|
| Sep 2503:49 UTC | SMS Delivery Delays from Twilio to Claro Brazil | minor | Ongoing |
| Sep 2502:24 UTC | SMS Delivery Delays from a Subset of Twilio Short Codes to Cellularone NE Arizona United States | minor | Ongoing |
| Sep 2420:40 UTC | Event Streams Service Disruption | minor | 5h 44m |
| Sep 2417:55 UTC | SMS Delivery Receipt Delays from a Subset of Twilio Alphanumeric Sender IDs to Ooredoo Algeria | minor | Ongoing |
| Sep 2417:19 UTC | Some Transfer Calls in Elastic SIP Trunking Failing With Error Code 32204 | minor | 43m |
| Sep 2416:22 UTC | Link Branding Creation Fails with HTTP 500 Internal Server Error (Auto SSL Enabled) | minor | 2h 4m |
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