Microsoft Outlook Hit by Exchange Online Service Outage

It certainly feels like a Monday, as thousands of Microsoft Outlook users have begun the work week unable to use the email service.

Downdetector, which tracks outages and problems for online platforms, showed a large spike in people reporting problems with Outlook around 8 a.m. PT on Monday. The site showed more than 6,000 reports of problems at 8:17 a.m.

A Microsoft representative told CNET the company is looking into the reports.

 Aug 31, 2026 6:58 PM ET 

Microsoft responds: 'We know this is disruptive'

Gael Cooper

Still facing issues with Microsoft Outlook or other services related to Microsoft Exchange Online? The company is aware, and is still working on a fix.

"We're aware of an issue affecting access to Exchange Online and some other services," a Microsoft spokesperson told CNET in an email on Monday afternoon. "We know this is disruptive for customers and we appreciate their patience while we work to restore services as quickly as possible. Updates are available on the Microsoft service health status page and @MSFT365Status ."

At 3:50 p.m., that status page offered some information, but no estimated time for a complete fix.

"We're reexamining recent changes made to the service to determine why the authentication components aren't being deployed as expected," the update read in part. "Additionally, we are exploring every avenue to safely restore the components, including reverting an update the affected infrastructure recently received. We're performing additional tests to determine whether this will provide relief."

Thousands of users have reported problems with Microsoft services, including Outlook, beginning Monday morning. At 3:25 p.m. PT, Downdetector shows over 2700 reports of problems.

Users were reporting a variety of issues, and many were unable to receive messages and access the app and website.

We're continuing to follow the outage and will share updates as they develop.

 Aug 31, 2026 4:25 PM ET 

Microsoft Outlook outage continues

Gael Cooper

If you're still wrestling with Microsoft Outlook, you're not alone. The problems that began around 8 am PT on Monday are continuing into the afternoon. Microsoft is continuing to post updates about the issue, which involves Microsoft Exchange Online and is preventing many people from using the popular Outlook program.

"We're continuing to fine-tune our remediation strategy as our internal tests progress," Microsoft posted to its Microsoft 365 Status account on X around 12:30 p.m. PT. "Additionally, we've confirmed that the authentication component issue impacts other services beyond Exchange Online."

A Microsoft representative told CNET earlier on Monday that the company was looking into the issues.

Problems seem to affect users in various ways. One Reddit user reported that problems hit accounts in their office at different times.

"Mixed results in office," another Reddit user wrote. "Some of us completely down, some working fine."

The errors seemed to evolve and change over time for some.

"Started earlier not getting my verification emails, now I get (an) error code when opening either app or browser," one Reddit user wrote.

At 1:27 p.m. PT, more than 4,000 people had reported problems to Downdetector. That number is slightly below the 6,000 reporting issues at 8:17 a.m. PT.

 Aug 31, 2026 9:51 AM ET 

It's not just you: Thousands are dealing with a Microsoft Outlook outage

Gael Cooper

The official Microsoft 365 Status account on X posted about the problem.

"We've identified an issue with an authentication component which is contributing to impact," the message reads. "To address this, we've developed a remediation strategy, and we're applying it to a portion of infrastructure to test its efficacy. Once we've confirmed this resolves impact, we'll apply the solution more broadly. For more information, please see EX1464935 in the admin center."

This means that Microsoft has officially opened an incident investigation for Exchange Online, and EX1464935 is the incident number. Many people will be affected via Outlook, because Outlook relies on Exchange Online for mailbox access and email delivery.

According to Downdetector, 37% of people reporting problems faced issues with receiving messages, 23% had trouble using the app and 20% reported issues with the website.

"Can't even open the site, when I could, I couldn't search or anything," wrote one Reddit user .

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