Microsoft is investigating an ongoing problem with Multi-Factor Authentication (MFA) that is preventing some customers from signing into their Microsoft 365 accounts.
“We are investigating an issue with multi-factor authentication that is preventing some users from accessing Microsoft 365 services. Additional information is provided in the admin center at MO287933, the company tweeted.
According to the company, only customers using on-premises Multi-Factor Authentication (MFA) servers are affected by this Microsoft 365 issue, and cloud authentication is not affected.
“We have identified 503 errors from specific processing components and are reviewing those errors to identify the source,” Microsoft said in the admin center.
“This problem could potentially affect anyone using MFA and either Network Policy Server (NPS) or Active Directory Federation Services (ADFS) to access Microsoft 365 services. This issue only affects local users and cloud-hosted users are not affected. “.”
We’re investigating an issue with multi-factor authentication preventing some users from accessing Microsoft 365 services. For more information, visit the admin center at MO287933.
– Microsoft 365 status (@ MSFT365Status) September 28, 2021
In a new update to the MO287933 admin center tracking ticket, Microsoft says that the issue has been resolved for some of the affected users.
“We scaled up the underlying infrastructure and received confirmation from a few previously affected users that the problem is now fixed for them. We are also seeing the service return to a healthy state, â€added the company.
“At the same time, we are continuing to investigate the underlying cause so that further action can be taken to ensure the problem does not recur.
We have taken steps to improve the performance of the affected infrastructure and we are beginning to see remedial action for affected users. We continue to look for a cause and closely monitor the service to ensure recovery is achieved. Admin center entry MO287933.
– Microsoft 365 status (@ MSFT365Status) September 28, 2021
In April, a global Microsoft Teams outage also prevented users from signing in to their accounts and sending and receiving messages that were already signed in.
Another large-scale outage in March had crippled several Microsoft services a month earlier, including Microsoft 365, Microsoft Teams, Exchange Online, Forms, Xbox Live and Yammer after widespread sign-in problems with Azure Active Directory.
In September 2020, Microsoft customers experienced another global outage with “transient†errors that also disrupted Office 365 and related services, including Microsoft Teams, Office.com, Power Platform, and Dynamics365.
To update: Microsoft says the MFA problem is now resolved.
We have completed scale-up activities on the underlying infrastructure to mitigate the problem and have confirmed to affected customers that the problem is now resolved. For more information, visit the admin center at MO287933.
– Microsoft 365 status (@ MSFT365Status) September 28, 2021
