Current status of Microsoft 365 services
Microsoft is currently working to resolve a widespread outage affecting Microsoft 365 applications. The disruption has lasted for more than 12 hours. While the impact varies between organisations, the most significant issues are occurring within Exchange Online, the system that manages business email and calendars.
Several attempts by Microsoft to apply technical fixes have not yet resulted in a full recovery. Users may find that services return briefly before becoming unavailable again. This instability also affects third-party applications that rely on Microsoft's infrastructure to function.
Potential causes and security
Microsoft has not confirmed the exact cause of this incident. In current communications, the company stated it has not ruled out a cyberattack. However, there is currently no evidence that customer data has been breached or exported. The primary issue remains one of service availability rather than data theft.
Outages of this duration are unusual for cloud providers. They often indicate a problem with the underlying domain name system (DNS) or a configuration error in the wide-area network that routes traffic to Microsoft's data centres. Until the company provides a formal Root Cause Analysis (RCA), the specific technical failure stays unconfirmed.
Internal actions for businesses
If your business is affected, you will likely see 'connection failed' messages in Outlook or find that the mobile app does not sync. During this period, we advise the following:
- Use local copies of files rather than attempting to open documents via OneDrive or SharePoint web interface.
- Avoid changing account passwords or re-installing software, as these actions will not resolve a server-side outage.
- Monitor official status pages, though these can lag behind the actual user experience during a major incident.
Ark Assist is monitoring the situation. We will provide further updates as Microsoft shares more technical information or confirms a reliable fix has been deployed.