An hours-long outage is preventing Microsoft's enterprise customers from accessing their inboxes, files, and video meetings.

Microsoft Corp. has been ramping up its cloud-based Exchange Online offering for its largest customers — even though that may mean cannibalizing its own on-premises Exchange Server installed base.

Downdetector logged 12,380 reports of an outage in Microsoft’s Outlook email service as of 12:15 p.m. Thursday; 15,745 reports of an outage in the Microsoft 365 suite of cloud applications as of 12:17 ...

CISA has issued an emergency directive ordering all Federal Civilian Executive Branch (FCEB) agencies to mitigate a critical Microsoft Exchange hybrid vulnerability tracked as CVE-2025-53786 by Monday ...