Microsoft Resolves Hourslong Teams, 365 Online Outage

The vendor investigated “errors within caching infrastructure” and “high CPU utilization on the components which process back-end navigation feature APIs” to resolve the issue.

Microsoft fixed a nearly six-hour-long issue with Microsoft 365 online applications and its Teams collaboration app Thursday.

The Redmond, Wash.-based vendor tweeted at 6:56 a.m. Pacific that it was “investigating access issues with Microsoft 365 Online apps and the Teams admin center.”

The company tweeted at 1:10 p.m. Pacific that it “received positive confirmation through our internal telemetry and impacted users that service has been restored.”

[RELATED: Amazon Alexa Down: More Than 15,000 Reports Of Outages]

Microsoft Teams Outage Fixed

CRN has reached out to Microsoft for comment.

Ookla’s Downdetector website noted thousands of reported M365 outages Thursday, with reports passing 3,000 at around 7 a.m. Pacific and reaching a high around 9 a.m. Pacific.

The vendor investigated “errors within caching infrastructure” and “high CPU utilization on the components which process back-end navigation feature APIs” to resolve the issue, according to Microsoft tweets.

Microsoft also added “further processing throughput within the affected environment” to improve service.

A screenshot shared online shows that users in North and South America felt “the majority of reported impact.” Although M365 apps weren’t rendering, users could still access the applications through web addresses, such as outlook.office.com for Outlook and teams.microsoft.com for Teams.

Updates shared to Reddit and NHSmail showed that users lost access to Excel Online, Office Online services’ search bars, the Teams administrator center, the SharePoint Online settings gear and the Yammer search bar.

A preliminary root cause was blamed on a caching infrastructure section “performing below acceptable performance thresholds, causing calls to gather user licensing information to bypass the cache and go directly to Azure Active Directory infrastructure resulting in high resource utilization, resulting in throttling and impact.”

This year has seen plenty of outages for multiple online services, including Twitter and Amazon Alexa. Microsoft itself saw outages in January and March.

However, nothing has compared to the massive outage Amazon Web Services experienced in December 2021.