The affected services included Outlook.com, Office.com, Power Platform, Dynamics365, and Microsoft Teams including Teams Live Event.
“A code issue caused a portion of our infrastructure to experience delays processing authentication requests, which prevented users from being able to access multiple M365 services,” Microsoft said in an update.
According to Down Detector, a website that tracks internet outages, users reported issues with logging in, server connection and Outlook globally.
The Microsoft 365 team said in a tweet on Wednesday: “We took corrective actions to mitigate the impact to ‘Exchange ActiveSync’ and have confirmed that service has been restored after users force a sync on their impacted devices”.
“Our investigation determined that corrective actions taken to address a previous issue have impacted ‘Exchange ActiveSync’. We’re applying a fix to mitigate impact. Users leveraging a legacy API will need to restart their devices”.
The tech giant said it was currently reviewing its code to understand what caused the code to “stop processing authentication requests in a timely fashion”.
In a separate incident, Microsoft said in a public Azure status update that a “subset of customers in the Azure Public and Azure Government clouds may have encountered errors performing authentication operations for a number of Microsoft or Azure services, including access to the Azure Portals”.
Microsoft attributed the Azure service outage to a “recent configuration change impacted a backend storage layer, which caused latency to authentication requests.”
