Slow delivery of emails to Microsoft servers ( 27/02/2026 )
Since Tuesday evening, February 24th, at 8 PM, we've been experiencing slower email delivery to Microsoft mail servers. This is impacting both consumer mailboxes (outlook.com, live.com, hotmail, msn, and other free mailboxes) and Microsoft 365 email services.
The outage is occurring at Microsoft. Several European mail server administrators have reported this on Microsoft's forums:
https://learn.microsoft.com/en-us/answers/questions/5786144/all-sending-ips-temporarily-rate-limited-(451-4-7?page=2#answers
We've contacted Microsoft support, but there's no resolution yet.
We'll continue to monitor this.
Update February 27 - 9:00 AM: We've seen a slight improvement in email delivery since this morning. The email queue has shrunk this morning, but there are still a lot of emails in the queue, resulting in slower delivery to Microsoft mail servers.
Update February 27 - 3:00 PM: All emails have been delivered from the queue. We will keep monitoring this in the next days.
