Tens of thousands of users were locked out of Microsoft Corp.’s suite of productivity tools on Thursday afternoon following a widespread service disruption that impacted Outlook, Microsoft 365, Teams, and Copilot.
User reports began spiking shortly after 12:30 p.m. ET, affecting both individual accounts and enterprise customers, according to outage tracker Downdetector. By 1:09 p.m. ET, reports of issues with Outlook alone peaked at nearly 130,000, while disruptions for the broader Microsoft 365 suite climbed past 47,000 shortly afterward. Thousands of users also flagged connectivity issues with Copilot, Teams, SharePoint Online, Word, and Excel.
In updates posted to its official Microsoft 365 Status account on X, the tech giant confirmed the disruption was tied to an “elevated load” across a portion of its infrastructure, which initially affected Exchange Online mailboxes in the Americas before expanding to impact service connectivity across multiple regions globally.
To restore access, Microsoft said it d all system deployments, began restarting affected servers, and started redistributing connection traffic across its broader global infrastructure to balance the load. The company noted it was also investigating an unexpected surge in a specific type of service traffic as a potential cause, though it did not immediately provide a timeline for a full recovery or respond to requests for comment.
By 1:50 p.m. ET, outage reports on Downdetector began trending downward, dropping to roughly 93,000 for Outlook and 37,000 for Microsoft 365. Thursday’s disruption follows another multi-day outage that plagued the Microsoft 365 suite in September.
“Everyone understands the importance of having out-of-band communications during a cyber incident, but as outages become an even more common business reality, that same principle needs to apply to any major disruption,” said Arvind Parthasarathi, CEO of CYGNVS. “When core systems like email and collaboration platforms go down, organizations can lose the tools they depend on to coordinate their response. Companies need a secure, independent environment where employees, executives and external partners can continue communicating, making decisions and managing recovery. Business resilience means being prepared to operate when the technology you rely on is unavailable.”