- Outlook was down for users over North America – and maybe other regions as well
- Login, server connections and sending/receiving mail were all affected
- The problem was attributed to “Unexpected High” CPU usage
A system interruption that affects Outlook users over North America, which is now resolved, caused users not to be able to access E emails and calendars via any Exchange Online connection method.
The problem traced as EX1151485 in the Admin Center was covered on the Microsoft 365 Status X page in a series of posts.
Microsoft stated that “the majority of previously broken infrastructure” had been “restored” about 14 hours after the first post went out, but the company chose not to share further details of the power outage.
Outlook has just come back online
The stop started early Thursday morning (September 11) Local Times, with users noticing problems across Outlook, Teams and Hotmail. Some also noticed OneDrive problems, but we are not sure if these are connected.
Login problems and server connection problems were the most important problems, but delays with the delivery of E email delivery also caused headaches for many.
Within hours of publishing his first X update, Microsoft reassured users that it was still “continuing to evaluate service -leemetry for potential irregularities in the system.”
DownDetector saw spikes in complaints relating to Microsoft 365 and Outlook Online, while the company’s public support page reported “Service degradation on Microsoft Consumer Products.” For Outlook, most complaints are related to login, with server connection and sending the receipt of some comments as well.
It later used some “optimizations” which caused “some service improvements” before they revealed that some users in South America had also been affected by the disruption.
The error has since been attributed to “unexpectedly high resource (CPU) utilization, which can contribute to connecting errors and errors for mailboxes hosted by this part of the infrastructure” determined by telemetry and track logs analyzed by Microsoft’s engineers.
Microsoft continues to monitor the problem for additional signs, but so far the services remain “within expected thresholds.”
