Microsoft has blamed a software code issue for the major outage that impacted several Microsoft 365 services, including Outlook, Office 365 and Teams on Tuesday.
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.”