CatalystOne incident

Issue with mail sent to Microsoft mail addresses

Minor Resolved View vendor source →

CatalystOne experienced a minor incident on February 26, 2026, lasting 232d 15h. The incident has been resolved; the full update timeline is below.

Started
Feb 26, 2026, 08:39 AM UTC
Resolved
Oct 17, 2026, 12:02 AM UTC
Duration
232d 15h
Detected by Pingoru
Feb 26, 2026, 08:39 AM UTC

Update timeline

  1. investigating Feb 26, 2026, 08:39 AM UTC

    We have identified that emails sent to hotmail.com, live.com, and outlook.com were temporarily blocked by our mail provider due to an issue on Microsoft’s side. The issue started on the evening of the 23rd and was resolved last evening. We are currently investigating whether the affected emails can be resent. Reference: https://learn.microsoft.com/en-us/answers/questions/5786144/all-sending-ips-temporarily-rate-limited-%28451-4-7