SEDNA Outage History

An application outage was identified affecting some Sedna customers on our Dublin 1 and Dublin 2 clusters between 7:30am and 08:00 am UTC and 9:20am and 09:35 and UTC. During this time, impacted users were unable to log in or access the platform. The issue is being treated as an emergency by our engineering team while service is being restored. We are continuing to monitor the platform closely to ensure stability and will keep you updated as the investigation progresses.

We are investigating reports of delayed mail between 10:20 am and 10:35 am GMT. We have implemented a corrective measure and are seeing normal mail delivery. Our engineering team is actively investigating the cause. We will provide further updates as soon as more information becomes available.

We are currently investigating an issue affecting mail ingress and egress globally. From 11:30 to 12:00 UTC some customers may have experienced delays or disruptions in email processing. Our engineering team is actively investigating the cause. We will provide further updates as soon as more information becomes available.

An outage affecting Sedna’s mail egress and ingress services has been identified on specific infrastructure EU clusters. Affected users are unable to send and receive mail. The issue is under investigation by engineering as an emergency.

We are continuing to investigate this issue, and will update every hour until it is resolved.

Microsoft Outage: Degraded Service Microsoft is currently experiencing degraded service functionality. As a result, recipients using Microsoft mailboxes may not receive emails, and messages sent from Sedna may result in NDRs. Updates on Microsoft’s Service Health Status can be found here: https://status.cloud.microsoft/m365

We are continuing to investigate this issue.

An outage affecting Sedna’s mail egress and egress services has been identified across our Virginia1 Cluster. Affected users may experience delays with sending and receiving mail. The issue is under investigation by Sedna's Engineering team as an emergency.

We are currently investigating this issue.

An outage affecting Sedna’s mail egress and ingress services has been identified on specific infrastructure EU clusters. Affected users are unable to send and receive mail. The issue is under investigation by engineering as an emergency.

Dear Customers, We’re currently experiencing a mail flow issue, which is causing emails to queue and may also impact incoming mail delivery. Our engineering team is actively investigating and working to resolve the issue as quickly as possible. We’ll provide updates as more information becomes available. Thank you for your patience and understanding.

As per Microsoft: ID: EX1144276 Issue type: Incident Status: Service Degradation Impacted services: Exchange Online Details: Title: Users may experience delays sending and receiving email messages User impact: Users may experience delays sending and receiving email messages. Current status: We're reviewing service monitoring telemetry to isolate the source of the issue and establish a fix. Scope of impact: Some users who are located in Europe attempting to send or receive Exchange Online email messages may be impacted. Next update by: Friday, August 29, 2025, at 2:30 PM UTC

Aug 29, 2025, 4:38 PM GMT+2 The new throttling rule has successfully been deployed. We’ve received confirmation from some of the previously affected users that they can now send and receive email. Additionally, our telemetry shows that the new throttling rule is having the desired effect and providing relief. Next update by: Friday, August 29, 2025 at 6:00 PM GMT+2

Aug 29, 2025, 5:38 PM GMT+2 After monitoring the service and receiving confirmation from previously affected users, we’ve confirmed that impact has been remediated. The service will now resume periodic attempts to deliver emails that were sent during the impacted period. Issue details Issue ID: EX1144276 Affected services: Exchange Online Status: Service restored Start time: Aug 29, 2025, 12:36 PM GMT+2 End time: Aug 29, 2025, 5:10 PM GMT+2 Issue type: Incident

We are currently investigating an issue impacting automatic mail forwarding in Exchange Online: Issue ID EX1072592. Affected users may experience delays or failures in receiving forwarded mail due to a fault within the Exchange system. Our Engineering team is actively investigating and closely monitoring the situation. We will provide further updates as more information becomes available

An application outage has been identified and is affecting customers on Dublin 1 infrastructure. Affected users are unable to log into or access the platform. The issue is under investigation by engineering as an emergency.

We are currently investigating this issue.

An application outage has been identified and is affecting all customers on Dublin 3. Affected users are unable to log into or access the platform. The issue is under investigation by engineering as an emergency.

Customers on our Dublin 3 cluster are experiencing a temporary delay in receiving mail. The issue is under investigation by engineering as an emergency.

users may experience issues with connecting their calendars in Sedna.