Microsoft says Outlook and Microsoft 365 access is disrupted

Microsoft is working to restore access to Outlook and other Microsoft 365 services after a disruption that began Thursday afternoon.

Microsoft 365 Status, the company's official service account, said at 12:54 p.m. Eastern it was investigating reports of users having trouble accessing Exchange Online mailboxes through multiple connection methods in the Americas. At 1:07 p.m., it said the issue may affect Microsoft 365 service connectivity for users in any region, so local readers who use Outlook or Microsoft 365 may be affected.

Microsoft later said a portion of its infrastructure is experiencing elevated load across multiple regions, which is likely contributing to the connectivity errors. In a 2:31 p.m. update, it said the elevated load is not driven by an increase in traffic, but by a number of servers being unexpectedly unavailable, straining the remaining infrastructure. The company said it is working to safely return those servers to service.

Microsoft said it has paused all deployments, is moving additional traffic off the affected infrastructure, and is restarting affected servers. The incidents are listed in the Microsoft 365 admin center as EX1550543 and MO1550821.

As of 2:44 p.m. Thursday, Microsoft had not said the Exchange Online and Microsoft 365 disruption was fully restored. Updates are posted on the Microsoft 365 Status account on X and at status.cloud.microsoft.