Microsoft 365 outage stretches into a second day as Outlook slowly recovers

Update, 7:45 a.m. ET Friday: The outage stretched into a second day. "Recovery actions are ongoing across affected Microsoft 365 infrastructure and progressing in phases," Microsoft said on X at 5:28 a.m. Eastern, adding that capacity "has not yet fully returned to baseline," USA TODAY reported. At 6:11 a.m. the company said traffic was being gradually restored and it was "seeing improvements in key scenarios, including mailbox access and delayed email processing, though some intermittent issues may continue." Downdetector showed about 15,000 Outlook problem reports around 6 a.m., down from roughly 130,000 at Thursday's peak, USA TODAY said. Microsoft has not given a time for full recovery.

SEATTLE (Nov. 12) — A widespread Microsoft outage cut off access to Outlook email, Teams and other Microsoft 365 services for many users Thursday, and the company said into the evening that its repairs were not working as quickly as hoped.

The problems began shortly before 1 p.m. Eastern time, CNBC reported, and about 130,000 users reported trouble with Outlook on the tracking site Downdetector at the peak. The Guardian reported that the reports also covered Word, Excel, PowerPoint, SharePoint and OneDrive, and that many people said they could not send or receive email or load their inboxes at all.

Microsoft first said part of its infrastructure was under elevated load across multiple regions. It later said a number of servers had become unexpectedly unavailable after failing automated health checks, straining the rest of the system, according to CNBC. By late afternoon the list of affected services had grown to include Planner, To Do, Intune, Defender for Office 365 and Purview, Engadget reported.

Around 4 p.m. the company said it had found an alternative health check that let some servers come back online. But a later status update said "our actions taken thus far have not provided the anticipated relief" and that a core process on the affected servers was becoming overwhelmed, The Register reported. The outage also took down administrator tools such as Intune and the Microsoft 365 Apps Admin Center, leaving IT staff unable to see what was wrong, The Register said.

In its latest update Thursday evening, Microsoft said servers it had returned to service could stop responding again once traffic reached them. The company said it was limiting some kinds of traffic in specific locations and rebuilding a group of servers with a previous software configuration to see whether that keeps them stable. It did not give a time for full recovery.