Microsoft 365 Service Degradation is affecting multiple services
Update
Microsoft 365 services have been restored.
Users may have been seeing degraded service functionality or have been unable to access multiple Microsoft 365 services.
For many, this will now be seen as delayed email messages appearing in their Inbox.
Here are the details that were posted by Microsoft.
Issue ID: MO1221364
Affected services: Microsoft 365 suite
Status: Service restored
Issue type: Incident
Start time: Jan 22, 2026, 2:33 PM EST
End time: Jan 23, 2026, 12:00 AM EST
User impact
Users may have seen degraded service functionality or were unable to access multiple Microsoft 365 services.
More info
Some of the impacted service functions included, but were not limited to:
- Sending and receiving email through Exchange Online, including notification email from Microsoft Viva Engage as well as subscription email for Microsoft Fabric users. Users may be receiving a "451 4.3.2 temporary server issue" error message when attempting to send or receive email through Outlook.
- Collecting message traces in Exchange Online.
- Searching within SharePoint Online, Microsoft OneDrive, and/or Microsoft Teams.
- Accessing the service portals, including Microsoft Purview, Microsoft Defender XDR, and the Microsoft 365 admin center.
- Creating chats, meetings, teams, channels or adding members in Microsoft Teams. Additionally, some users may have been unable to create breakout rooms or Microsoft Teams live events.
- Receiving presence or location information in Microsoft Teams.
- Existing or new meeting options for Facilitator in Teams may not have been honored.
- Applying and managing sensitivity labels, interactive operations on reports, and artifacts with sensitivity labels in Microsoft Fabric.
- Print registration and printer jobs may have failed in Universal Print.
- Microsoft To Do users may have experienced synchronization issues, preventing tasks from updating across devices. Additionally, tasks created in Shared Lists may not have appeared for collaborators.
- Microsoft Defender for Cloud Apps users may not have been able to view insights or view, create, or update OAuth enabled app policies. Reporting data may have also appeared blank, even though no errors were shown.
- Microsoft Defender for Office (MDO) users may have experienced limited access to administrative and SOC experiences, including the quarantine portal and Safe Links protection.
- Microsoft Power Automate users may have been unable to utilize Power Automate connectors including Office 365, Office 365 Users, Office 365 Groups, and Office 365 Groups Mail.
Scope of impact
Any users served through an affected section of service infrastructure in the North America region may have been intermittently impacted. This could have affected users located in Asia-Pacific, Europe, or Latin America.
Preliminary root cause
We identified that the issue was caused by elevated service load resulting from reduced capacity during maintenance for a subset of North America hosted infrastructure.
Current status
Jan 23, 2026, 1:27 AM EST
We’ve confirmed that the affected infrastructure has returned to a healthy state and is operating as expected. We’ll continue to closely monitor the remediation actions taken and make any necessary adjustments to maintain stability. If users experience any residual issues, clearing local DNS caches or temporarily lowering DNS TTL values may help ensure a quicker remediation.
Microsoft is aware of an issue currently affecting a number of core services,
At Queen's we are getting reports of errors when sending email, delays in the delivery of email and problems accessing management portals related to Office 365.
Microsoft has provided the following details concerning the degradation.
Users may be receiving a "451 4.3.2 temporary server issue" error message when attempting to send or receive email through Outlook.
Some of the impacted service functions include, but may not be limited to:
Sending and receiving email through Exchange Online, including notification emails from Microsoft Viva Engage.
Collecting message traces may be delayed or fail.
Searches within SharePoint Online and/or Microsoft OneDrive mail be delayed or fail to complete.
Accessing the service portals, including Microsoft Purview, Microsoft Defender XDR, and the Microsoft 365 admin center.
Current status: We're continuing to review what actions are required to restore the affected infrastructure to a heathy state and rebalance the service traffic to achieve recovery.
Scope of impact: Any users served through an affected section of service infrastructure in the North America region may be intermittently impacted.
Root cause: A portion of dependent service infrastructure in the North America region isn't processing traffic as expected.
This ITS notification will be updated as more information becomes available.