Microsoft Outlook was down? Live tracking multi-hour email outage

When you buy through links on our articles, Future and its syndication partners may earn a commission.

Microsoft Outlook may be suffering an outage. Reports about the email platform started popping up on the outage-tracking site Down Detector starting around 8:30 am Pacific.

It peaked around 9:30 am around 6,000 reports. The outage appears to be affecting access to mailboxes, delays in sending emails or failure to send.

Outlook stayed down for nearly 12 hours, last until about 8:30 pm Pacific. A fix was implemented around 6 pm that seemed to get people back online but it didn't completely work and some functions like search didn't work properly for two more hours.

According to the Microsoft 365 status page, the outage was caused by "an issue within a core authentication configuration used by multiple Microsoft 365 services is resulting in impact."

We did not see any more specific information beyond that.

Here's what we know:

August 31, 2026 – 2:26 PM

Multi-hour outage

Reports starting appearing on Down Detector around 8:30 am Pacific but didn't peak until an hour later.

As of this posting, there are more than 5,000 reports on the outage tracker and no sign of decline.

August 31, 2026 – 2:28 PM

Microsoft says all systems "operational"

I've checked the Microsoft 365 status page , and according to that page every Microsoft product is operational.

August 31, 2026 – 2:31 PM

M365 Twitter account acknowledges problem

While the Microsoft 365 status page isn't showing any issues, the official Microsoft 365 Status X account did acknowledge the issue.

"We've confirmed that users may experience degraded functionality with various Exchange Online functionalities. We're reviewing service telemetry and diagnostic data to isolate the source of the issue. For more information, please see EX1464935 in the admin center," the post reads.

August 31, 2026 – 2:34 PM

What issues are we seeing?

Based on comments from Down Detector and X, the most common issue appears to be a failure to actually send and receive emails for those who can get in.

I've seen several comments saying that the app won't even open on their computers.

"Not receiving emails since about 10:45 am, then went downhill, replies stopped coming through, then emails came to a halt, and then, besides Outlook constantly freezing, now my shared work folder is no longer showing me emails and gives an error," one said.

For those in businesses, it appears they can't even send messages between connected emails.

August 31, 2026 – 2:40 PM

Users "may experience a variety of symptoms"

If you can get in the 365 Admin Center, this is the message you should see:

"Users may be unable to connect to, or experience degraded functionality with Exchange Online

Users may experience a variety of symptoms related to this event, including but not limited to:
- Delays, failures, or incomplete results when searching for content within Exchange Online mailboxes.
- Delays or failures when sending or receiving email messages.
- Authentication-related errors when accessing Exchange Online services.
- Difficulties accessing or performing actions within Exchange administration experiences.
- Intermittent failures affecting mailbox operations and message delivery workflows."

August 31, 2026 – 2:51 PM

Slow decline

Over on Down Detector, reports have started to decline.

The peak around 9:30 a.m. was around 6,000 reports. As of 11:45 a.m. Pacific, reports are closer to 4,500.

I've seen some people in offices say that portions of their teams are able to access the email platform, but some of the team is still down.

August 31, 2026 – 3:09 PM

No updates from Microsoft

Other than the couple tweets and the Admin Center update, we haven't seen any other updates from Microsoft.

It's not clear what work is being done to resolve the outage.

August 31, 2026 – 3:26 PM

Is Outlook down for you?

Let us know in the comments what issues you're experiencing.

August 31, 2026 – 3:44 PM

Outage has last 4 hours

With no updates from Microsoft, today's Outlook outage has lasted for more than four hours.

As of this posting, despite declining reports it's not clear when the outage might end.

August 31, 2026 – 3:52 PM

Update from Microsoft

On the M365 status page , a new update just popped up.

Here it is:

OneDrive for Business and SharePoint Online: Users may be unable to load or refresh portions of OneDrive and SharePoint, including account and storage information, search results, Favorites, Followed and Shared With Me content, recent files, lists, and news. Some users may also experience delayed or failed file opening, Office policy-label retrieval, OneDrive synchronization, mobile camera upload, and video playback. Users may see partial page failures, missing or stale content, repeated retries, and operation timeouts rather than a complete platform outage.

Exchange Online: Users may be unable to connect to, or experience degraded functionality, with Exchange Online. All connection methods are affected.

Microsoft Teams: Users may experience issues with calendar functionality and search. Users' presence may be stale and not update automatically or through manual adjustment. User location adjustment may fail.

Microsoft Purview: Users may face intermittent authorization failures across solutions in Purview. Purview admins can't access the portal. Additionally, in Microsoft Purview Communication Compliance, users may see errors when loading Communication Compliance policies and Data Loss Prevention (DLP) policies. Communication Compliance policy creation and evaluation may be delayed.

Microsoft Defender XDR: Users may experience intermittent authorization failures across solutions in Defender.

Current status:We're continuing to perform comprehensive tests to ensure our mitigation strategy effectively resolves the issue without introducing additional impact. In parallel, we're exploring alternative remediation avenues to minimize impact in the interim.

Scope of impact:Users attempting to perform any of the outlined impact scenarios may be affected by this event.

Preliminary root cause:An issue within a core authentication configuration used by multiple Microsoft 365 services is resulting in impact.

August 31, 2026 – 4:14 PM

Snail mail

Not much new to share with you but this message from a frustrated user on Down Detector gave me a chuckle.

"Now distributing stamps & envelopes to our team. Printer is working overtime."

August 31, 2026 – 4:39 PM

Outage appears international

Users reporting in on Down Detector are claiming to be from all over the country including New York, Las Vegas, Kentucky, Indianapolis and more.

I'm also seeing some reports from other countries including Guatamala City, Montevideo, Uruguay and Argentina.

August 31, 2026 – 5:23 PM

Where we stand after 6 hours

Unfortunately, pretty much the same.

The M365 status page had a recent update that shows Microsoft's engineers are working on the issue but it doesn't appear relief is coming any time soon.

"Current status: We're reexamining recent changes made to the service to determine why the authentication components aren't being deployed as expected. 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."

Reports on Down Detector have declined but I think that's more because people on the East Coast are starting to log off for the day.

August 31, 2026 – 6:07 PM

Slow decline but still thousands of reports

As mentioned in my last post, the reports on Down Detector have been in a steady decline, but there are still thousands of reports. Currently, it's sitting around 3,100.

There are certainly people using Outlook for personal reasons, but I think reports will decline as people across the US start to log off from work.

August 31, 2026 – 6:41 PM

A different update from Microsoft

A user on Down Detector shared an alleged update from Microsoft.

Here's what it says:

We're continuing our targeted review of affected infrastructure and recent changes made to the service to definitively confirm the cause of impact. We're additionally continuing to test and implement various mitigation strategies to apply the necessary authentication component, which have so far yielded positive results. We're monitoring these tests and mitigative actions closely and will provide an estimated time to resolution as soon as one is available.

We understand the impact that events like these can have for your organization and we appreciate your patience as we work to mitigate this issue with the highest priority.

August 31, 2026 – 7:19 PM

Fixes may be in the works

It finally seems that Microsoft may have mitigations in place. Though the company has not yet provided an estimated time for a return to normal service.

" We're continuing to implement a targeted mitigation to re-apply core authentication components, and we're expanding this action more widely across the affected environments as we closely track the recovery of affected downstream scenarios. Users may notice gradual recovery to the scenarios identified in the "More info" section as our mitigation action takes effect in their corresponding sections of infrastructure, and we're continuing to review whether any additional actions may be required to achieve withstanding recovery across all affected scenarios. We'll provide an estimated time to resolution as soon as one is available."

August 31, 2026 – 7:45 PM

Reports continue to decline

Reports on Down Detector continue their steady decline but we are hewing closer to 5 pm on the West Coast, where it's likely people are starting to logoff there and I expect reports will take a nosedive over the next hour.

Microsoft still hasn't provided an ETA for a return to normal service.

August 31, 2026 – 8:23 PM

Microsoft response

I reached out to Microsoft to see if they could provide an ETA or any kind of update. Unfortunately, I received neither.

Here's what I was told by a Microsoft spokesperson:

"We're aware of an issue affecting access to Exchange Online and some other services. 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 ."

August 31, 2026 – 8:37 PM

Latest update from status page

Here's the latest update from the Microsoft status page:

We're progressively restarting targeted sections of affected infrastructure to ensure the re-applied authentication components are effectively implemented across affected services. We expect this will aid the recovery of affected scenarios. Users should expect delayed delivery of backlogged messages and residual impact across downstream scenarios as these actions are continuing. We'll provide an expected recovery time as soon as one becomes available to us.

Still no ETA, but you might start seeing some recovery.

August 31, 2026 – 9:05 PM

Taking a break

This is Scott. Reports on DD have fallen below 1,000 since before 8 am Pacific. However, based on the Microsoft site its not over.

I'm taking a brief dinner break. I'll be back soon with more updates.

August 31, 2026 – 10:08 PM

Email should be recovered

The most recent update from Microsoft indicates that your email should have returned to normal. Though the status says that some parts of the system aren't recovering properly so you may have issues with things ilke search.

"Users can expect to see continued recovery to email delivery, while users may see residual impact to downstream and dependent scenarios, including search, across affected services. "

August 31, 2026 – 10:40 PM

Reports are under 500

With some recovery in effect, reports are under 500 on Down Detector and I'm seeing a several comments from people who have regained access to their accounts.

However, I am also still seeing some comments from people who can't sign in or aren't getting emails.

There is still not ETA for a full recovery and as mentioned earlier, some aspects, like search, aren't working properly.

August 31, 2026 – 11:55 PM

Calling it

Well folks, I'm going to call this outage.

The reports are under 200, and the status page just updated with this notice:

"We're observing widespread recovery to Exchange Online mail connectivity, though the draining of backlogged mail queues may take longer for some organizations due to the volume of previously queued messages. Our recovery efforts are now focused on re-applying our targeted authentication component fix and restarting certain instances of infrastructure correlated with search functionality to ensure the full restoration of the associated scenarios."

With that settled, this outage appears to finally be over.