Microsoft 365 is down for many users worldwide. Here’s what’s affected (Outlook, Exchange, Teams, Copilot), what Microsoft says caused it, recovery status and what to do meanwhile.
Microsoft 365 is down for many users worldwide. Here’s what’s affected (Outlook, Exchange, Teams, Copilot), what Microsoft says caused it, recovery status and what to do meanwhile.
Stacey
Yes, Microsoft 365 is having a major global outage, and it is mostly an email problem. Since about 1:26 p.m. ET on Thursday, Nov. 12 (5:26 a.m. Friday in Sydney), many users have been unable to open Outlook, send or receive mail, or use features that depend on Exchange Online, Microsoft’s cloud email service. Teams, SharePoint and Microsoft 365 Copilot were also hit. Microsoft says it is not a cyberattack, servers are slowly coming back, and queued email should arrive late rather than be lost. Here is what is down, what caused it and what you can do while you wait.
Microsoft is tracking the problem as incident MO1550821, titled “Users may be unable to connect to multiple Microsoft 365 services.” According to the incident text mirrored on the University of Pennsylvania’s Microsoft incident feed, users may be unable to reach their mailbox through Outlook on the web, Outlook desktop, Exchange ActiveSync (the protocol most phone mail apps use) or REST-based connections, and email delivery may be delayed.
The University of Queensland’s status page lists the services its staff and students saw affected:
Malaysian tech site SoyaCincau also lists Microsoft Defender XDR and Universal Print as potentially affected. As the incident went on, Microsoft narrowed the picture: features that talk to Exchange Online are the ones breaking, while parts of those apps that do not depend on email keep working.
Partly. Microsoft said Teams chats and online meetings “remain largely functional,” but scheduling meetings and creating new chats can fail because those actions touch Exchange, the Guardian’s live coverage reported. Microsoft earlier said it had restored Teams problems in North America, though some people still reported connection errors.
Downdetector showed a spike of nearly 130,000 reports worldwide, with people unable to use Word, Excel, PowerPoint, Outlook, Teams, SharePoint and OneDrive, the Guardian reported. Reports fell to about 13,000 five hours later, but many users still could not send or receive email or load their inboxes.
The timing hit Australia and New Zealand hardest, because the outage began just before their Friday workday. Australian courts in South Australia and Victoria reported email problems, schools told parents to phone instead of emailing, Service NSW asked customers to delay visits to its centres, and Home Affairs Minister Tony Burke said the federal police and security agencies were also affected. The Australian Medical Association said some facilities went back to paper scripts because logging in to prescribing software needs email-based multifactor codes, but patient care was not affected.
The outage also broke connectors that link AI tools to Microsoft 365. OpenAI said new connections to its Microsoft connectors might fail, and Anthropic said an upstream provider issue was affecting its Microsoft 365 connector.
Microsoft first said part of its infrastructure was “experiencing elevated load,” and then found that a number of servers had become “unexpectedly unavailable” after failing automated checks. That pushed extra traffic onto the servers that were left, which made things worse.
In a later update, the company said a process on the affected servers that is “responsible for establishing secure connections becomes overwhelmed, causing the servers to stop processing requests.” Microsoft said it was preparing a configuration fix, testing it on a subset of servers before applying it more widely, and in parallel rolling back a recent network configuration change that “correlates with the start of impact.” It also paused other deployments and configuration changes while it investigates. Microsoft has not published a confirmed root cause yet.
Mark Gregory, an associate professor at RMIT University’s School of Engineering, told the Guardian it looks like “a cascading problem”: when part of a server pool drops out, every user piles onto the rest, those overload and fail too. He compared it to the configuration error behind Australia’s 2023 Optus network outage.
Microsoft and the Australian government both said there was no sign of a cyberattack. Burke said Microsoft described it as an update gone wrong, similar in some ways to the 2024 CrowdStrike incident. If your PC is showing a crash screen rather than just failing to load email, that is a different problem; our guide to troubleshooting the Blue Screen of Death in Windows 11 covers that.
Microsoft has not given a time for full recovery. Its updates say restarted servers are holding steady, traffic is being shifted to other network gateways, and protective traffic limits are being used in specific locations before more connections are let back in. Recovery is gradual, region by region, so some people get mail back hours before others. Early on, Microsoft said servers it returned to service became unresponsive again once traffic came back, which is why it is moving slowly.
The good news for anyone waiting on an important message: queued email is expected to be delivered, just late. You can follow the official Microsoft 365 service health page; IT admins can open incident MO1550821 in the Microsoft 365 admin center for the full timeline.
This is the second big Microsoft disruption in a short span: the company reported an outage of its Azure cloud platform last month that also knocked out its productivity apps. For small businesses that run everything through one provider, it is a good moment to look at backups, as we cover in our guide to cloud data management.
Outlook and other Exchange Online services have been degraded since about 1:26 p.m. ET on Nov. 12. Microsoft is restoring servers gradually, so check the Microsoft 365 service health page for the current status in your region.
No. Microsoft said it had “no indication of a cyber-attack,” and Australian officials said the same. The problem traces to overwhelmed servers and a recent network configuration change.
Microsoft has said queued email is expected to be delivered, though with a delay. Senders may also get delay notices.
Microsoft’s service health page showed degradation on both Microsoft 365 business and enterprise services and Microsoft consumer products, so some personal accounts may see problems too.
The outage is tracked as MO1550821 in the Microsoft 365 admin center.
Featured image: Building 92 of Microsoft’s Redmond campus, by Jiaqian AirplaneFan via Wikimedia Commons, licensed under CC BY 3.0.
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