From the Guardian · · 1m 50s
Microsoft 365 outage hits millions globally
A configuration update caused Microsoft 365 to go down for over nine hours, affecting businesses, governments and schools worldwide.
In brief
A configuration update caused Microsoft 365 to go down for over nine hours, affecting businesses, governments and schools worldwide. Microsoft 365 went down for more than nine hours after a configuration update overloaded servers, affecting millions of users including government agencies and schools. Originally…
Microsoft 365 goes down globally
At around six pm UTC on Thursday, Down Detector showed nearly one hundred thirty thousand reports of Microsoft 365 outages affecting Teams, Word, Excel, PowerPoint and Outlook.
Outage lasts more than nine hours
The outage affected businesses, government agencies and even Microsoft employees unable to email during the more than nine hours of downtime.
Configuration update caused the problem
A configuration update resulted in some servers becoming overloaded and taken offline. When Microsoft attempted to apply a fix, servers that came back online became unresponsive.
Traffic overwhelmed remaining servers
As some servers went down, traffic was funnelled onto remaining servers, causing traffic issues for those still online. Microsoft began limiting traffic to affected servers.
Email service most severely affected
As of two am Friday UTC, Microsoft had narrowed down most issues to Microsoft Exchange, the email service behind Outlook. Teams meetings and chats had returned to service.
Australia hit hardest by outage
Many people in Australia reported being unable to access their inboxes on Friday morning. Councils, state and federal government agencies, courts and schools were not contactable by email.
Not a cyber-attack, Microsoft says
Microsoft ruled out a cyber-attack as the cause, saying there was no indication the outage was a new attack on critical infrastructure.
Test updates and maintain backups
RMIT associate professor Mark Gregory said organisations should thoroughly test updates before deployment and maintain backup options such as Google's Gmail or LibreOffice.
The headline
Microsoft 365 went down for more than nine hours after a configuration update overloaded servers, affecting millions of users including government agencies and schools.
