Security News > 2021 > March > Microsoft 365 outage knocks down Teams, Exchange Online
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Starting at approximately 3:34 PM EST, users began reporting being unable to login to their Microsoft 365 accounts, Microsoft Teams, or access other Microsoft apps.
"As a result of the issues currently facing Azure AAD, we are currently experiencing problems on the Microsoft Tech Community with login and authentication. This will result in users being unable to login and users already logged in getting unexpected errors as sessions timeout," posted a Microsoft Tech Community manager.
Microsoft has acknowledged the outage in the Microsoft 365 incident report MO244568, which states the outage initially impacted Microsoft Teams but is now affecting other services.
"Initial reports indicate that primary impact is to Microsoft Teams; however, other services including Exchange Online and Yammer are also impacted."
Microsoft has confirmed that the widespread outages affecting Microsoft's online services are the result of an Azure Active Directory configuration issue.
This issue is preventing users from authenticating to Microsoft 365, Exchange, Online, Microsoft Teams, or any other service relying on AAD. "Starting at approximately 19:15 UTC on 15 Mar 2021, a subset of customers may experience issues authenticating into Microsoft services, including Microsoft Teams, Office and/or Dynamics, Xbox Live, and the Azure Portal," reads the Azure status page.
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