Hours-long Microsoft outage disrupts businesses, governments globally

A more than 12-hour outage ​of Microsoft Outlook and Teams crippled communications for businesses and governments globally on Friday, forcing some organizations to revert to fax machines and halting ‌at least one bond repurchase in Europe.

Microsoft (MSFT.O), opens new tab said server issues were behind the incident that also affected its Copilot AI assistant and that a broader roll-out of software fixes was starting to stabilize the system. It said it was not aware of any malicious activity.

Outlook and Teams are two of the most widely used workplace applications with hundreds of millions of users. The outage prevented people from performing essential ​functions such as sending emails, managing calendars and hosting virtual meetings.

It affected government agencies from Australia to Japan and the United States, caused delays at trading firms, ​hindered some companies from publishing earnings and prompted airlines to warn customers of communication lags, according to public statements.

Organizations that host Microsoft ⁠services on their own servers, rather than in the cloud, were somewhat spared.

The outage is one of the longest in Microsoft's history and the second disruption to ​its services this year.

Microsoft said the outage specifically hit features tied to Exchange Online - its cloud-based email and scheduling hub - leaving unconnected applications operational.

The incident deepens questions about the global reliance on ​a handful of Big Tech companies that supply both the essential software and the cloud infrastructure that underpins it.

Microsoft shares fell 1.7% before the bell, lagging the broader market. They have gained roughly 8% so far this year.

"The bigger worry is that this is not the first Microsoft 365 outage this year," said Josh Gilbert, a market analyst at trading platform eToro.

"If reliability starts to look like a ​recurring problem, it hands every IT department a reason to think twice before putting even more of their business in one provider’s hands."