Microsoft is investigating a new Microsoft 365 outage affecting multiple services across North America, including the company’s Teams collaboration platform.

Since the incident started over two hours ago, outage monitoring service Downdetector has received thousands of user reports, with most affected users saying they’re experiencing server connection and website problems when trying to access Microsoft 365 services and features.

“We’re investigating an issue impacting multiple Microsoft 365 services and features in the North America region,” Microsoft confirmed via its official Microsoft 365 Status Twitter account.

In a service alert (MO1068615) in the Microsoft 365 admin center, the company says impacted services include but are not limited to Microsoft Teams, adding that the most likely cause could be a faulty routing configuration for its Azure Front Door (AFD) cloud content delivery network.

“We’re reviewing Azure Front Door (AFD) routing configurations and networking telemetry to isolate the source of the issue,” Microsoft added.

“We’ve identified a section of AFD infrastructure is performing below acceptable thresholds. We’re rerouting traffic to alternate infrastructure to mitigate impact. Meanwhile, we’re also taking mitigation actions to expedite recovery of the Microsoft Teams service.”

While the company has yet to share more information on the outage’s root cause and how widespread it is, Microsoft tagged this as a critical service issue in the admin center, which typically involves noticeable user impact.

​In March, Redmond mitigated another outage that affected Teams customers, causing call failures and impacting other services such as Outlook, OneDrive, and Exchange Online, preventing users from checking email messages.

The same month, it addressed an issue that prevented Outlook on the web users from accessing Exchange Online mailboxes and a week-long Exchange Online outage that caused delays and failures when sending or receiving email messages.

More recently, in April, Microsoft fixed an issue blocking IT admins worldwide from accessing the Exchange Admin Center (EAC).

Update May 06, 11:31 EDT: Microsoft says the outage has been mitigated and that it also affected SharePoint Online and OneDrive for Business customers.

A final admin center update added that the root cause was higher than normal CPU usage across systems part of Microsoft’s AFD infrastructure.

“A small section of AFD infrastructure started to perform below acceptable thresholds. We have identified high Central Processing Unit (CPU) utilization as a potential contributing factor that resulted in impact. Further investigations are ongoing and more detail will be provided within the Post-Incident Report,” it said.

“We’re isolating the source of the high CPU utilization so that action items can be identified to prevent impact reoccurring.”