Microsoft Outage Disrupts Outlook and Teams Into a Second Day

The disruption began at 11:17 a.m. Eastern Time on Thursday, when Microsoft opened an Exchange Online incident after users lost access to their mailboxes.

Microsoft first located the problem in the Americas, then warned that connectivity could fail “in any region.”

Servers Fail Health Checks

Microsoft initially blamed “elevated load” on its infrastructure, then said the strain was not caused by a surge in users.

A large number of servers had become “unexpectedly unavailable” after failing automated health checks, shifting work onto those that remained. A core process on those servers later became overwhelmed and cut capacity.

Recovery attempts repeatedly failed to hold. Servers brought back online became unresponsive once traffic returned.

Charles Lamanna, Microsoft’s executive vice president of Copilot, Agents and Platforms, said there was “no indication this is the result of malicious or cyber activity.”

The outage has hit Microsoft 365 services that interact with Exchange Online, including Outlook, Teams, Copilot, SharePoint and OneDrive. Services that do not depend on Exchange have continued to function.

Governments and Banks Feel the Strain

Downdetector said problems spread to 74 countries and territories within about an hour, peaking at 19,650 reports a minute.

New Zealand’s foreign ministry said email was disrupted at its embassies and consulates, and Immigration New Zealand paused visa processing. In Singapore, the Government Technology Agency said government email was down, while DBS, UOB and OCBC warned of delays in customer replies.

In Britain, the GMB union said the outage was having a “serious impact” on the National Health Service, and several police forces asked the public to report crimes by telephone. Japan’s government said its information systems were affected.

The Swiss Army has already moved to drop Microsoft software over espionage concerns, a reminder of how widely the company’s tools are embedded in public institutions.

Courts, Markets and Airlines Disrupted

The Philippines’ Supreme Court said some operations, including email responses, were affected. In New Zealand, a scheduled teleconference at Hamilton District Court could not go ahead.

Euronext told listed companies to use the telephone after its listing teams lost email. OpenAI and Anthropic reported problems with Microsoft 365 connectors.

Indian carriers including IndiGo, Air India and Akasa Air said email support was disrupted but flight operations were not. SpiceJet reportedly cancelled three departures from Delhi and delayed two others.

Recovery Remains Uneven

By Friday morning, Microsoft said it was seeing “early signs of stabilization,” but service capacity had “not yet returned to normal levels.” It extended the email timeout window to 48 hours to protect delayed messages.

A later Friday update said mailbox access was improving, though intermittent issues may continue. Microsoft has not given a time for full restoration.