The configuration change has fully saturated in all affected infrastructure. Microsoft verified that the service is healthy by monitoring telemetry and confirming resolution with previously affected customers.
Posted Jul 10, 2025 - 19:49 UTC
Identified
Update from Microsoft:
Microsoft begun a broad expedited deployment of the configuration change across all affected infrastructure. They expect most impacted users will experience relief within the next two hours, as the fix saturates the environment. They are closely monitoring service health telemetry to ensure the recovery continues as expected. They understand how impactful incidents of this type can be for your organization, and they are continuing to open any additional workstreams to expedite recovery and restore availability.
Posted Jul 10, 2025 - 16:39 UTC
Investigating
Microsoft Service Incident - EX1112414
Scope of impact: Users attempting to access their Exchange Online mailbox using any connection methods may be impacted.
Preliminary root cause: A recent service update to an authentication component is unintentionally preventing access for a subset of users, resulting in intermittent service unavailability.
More info: Impacted connection methods include, but may not be limited to: - Representational State Transfer (REST) API - Outlook on the web - Exchange ActiveSync (EAS) - Messaging API (MAPI)
Update: Microsoft is continuing to apply the configuration changes to fix the underlying problem and completing additional validation efforts to ensure authentication components are properly configured. In parallel to the current deployment of the configuration change fix, they are reviewing options to leverage an expedited deployment methodology in regions which are experiencing the highest levels of impact to provide the most effective relief where possible.
Posted Jul 10, 2025 - 15:08 UTC
This incident affected: Zix - Cybersecurity (Zix Microsoft Office 365).