Resolved Service Disruption

This incident has been resolved.

Resolved: An issue impacting authentication and system responsiveness for a subset of end-users and administrators accessing Microsoft Office 365 has subsided. Further investigation of the issue found the errors were correlated with a service degradation reported by Microsoft. Microsoft reported this is related to mitigation activities form yesterday's service disruption (MO147606): "We identified and reverted an update that was causing multiple services to be throttled. We're conducting tests to ensure that impact has been resolved. Further updates can be found in the admin portal under EX147785 and MO147789."