Microsoft struggles to restore Outlook, Teams, and other services as global outage enters second day

Microsoft is grappling with a massive service outage that has disrupted Outlook, Teams, and other applications globally for over two days. The company has not found any evidence of a cyber-attack, stating it is still investigating the issue. Down Detector recorded nearly 150,000 reports of users unable to access various Microsoft 365 services, including Word, Excel, PowerPoint, Outlook, Teams, Copilot, and more, starting on Thursday morning.

Microsoft confirmed the outage, noting it was investigating reports of users experiencing difficulties accessing Exchange Online mailboxes through multiple connection methods. The company suspected that elevated server load was contributing to connectivity errors.

By the evening, Microsoft managed to restore some services, but over 10,000 people were still unable to access key services. One of the worst-affected services was Outlook, with users reporting they could neither send emails nor access their inboxes. Microsoft stated it was attempting to mitigate connectivity issues by restarting and validating affected servers, as well as assessing if recent configuration updates were causing the problems. However, some servers put back into service became unresponsive again once they received traffic.

Microsoft is analyzing diagnostic data from unresponsive servers and temporarily limiting certain types of traffic to affected infrastructure in some regions. The outage has impacted not only general users and global organizations but also AI companies like Anthropic and OpenAI, which use Microsoft 365 at their offices and have reported severe connectivity issues.

While Microsoft has not provided key details about the outage, some experts believe it may be affecting the network layer in Microsoft's systems, potentially similar to a configuration issue that caused Optus's network outage in 2023. If the issue persists, overloaded servers could crash due to being unable to handle the increased traffic.