If your inbox went quiet on Thursday afternoon, you weren't alone.
A global Microsoft 365 outage took Outlook offline for users in at least 74 countries on 12 November 2026, with Teams, Copilot, OneDrive and SharePoint also disrupted. By Friday morning, services were only partly restored.
For most SMEs, Microsoft 365 is the office: email, calls, files and meetings all run through it. So when it goes down, work stops. Here’s what happened, what to do if Outlook is still down for you, and how to make sure the next outage doesn’t stop your business.
What happened in the Microsoft outage?
The problems began late on Thursday afternoon, UK time. Outlook was hit first and hardest, with users unable to open their mailboxes on the web, desktop or mobile. Downdetector reports peaked at more than 131,000, and around 7,900 UK users were still reporting Outlook problems on Friday morning.
Microsoft says a component that checks server health failed, wrongly flagging servers as unavailable. That pushed their traffic onto the remaining servers, which became overloaded. As servers came back, they were swamped by devices reconnecting and fell over again. That’s why recovery has been slow and patchy.
The disruption reached well beyond office inboxes. Government systems in Japan and Singapore were affected, and closer to home, Hertfordshire Police asked non-emergency callers to use 101 while online services were hit.
Was it a cyber attack?
No. Microsoft says there is no indication of malicious or cyber activity. This was a technical failure inside Microsoft’s own infrastructure. That matters, because it shows outages don’t need a hacker. Even the world’s largest cloud provider can go down on its own.
Where things stand
As of Friday morning, 13 November, Microsoft reported “early stabilisation” but said capacity was not yet back to normal. It has extended the Outlook email timeout to 48 hours, so emails sent during the outage should still arrive, though they may land in batches.
Is Outlook still down for you? What to do now
- Check the official status first. Admins can see live updates in the Microsoft 365 admin centre under Health > Service health. Look for incident EX1550543 (Exchange/Outlook) and MO1550821.
- Don’t start changing settings. Resetting passwords, reinstalling Office or changing DNS won’t fix a Microsoft-side outage and can cause new problems once service returns.
- Use what’s still working. The Outlook desktop app may still show email you’d already downloaded. Teams chat and calls largely kept working during this outage.
- Tell clients and suppliers. A quick text, phone call or social post stops people assuming you’re ignoring them.
- Watch for phishing. Scammers are already sending emails and texts telling people to “reset your password” or “click here to restore Outlook”. Microsoft will never ask you to do this. Don’t click.
- Check for missing emails afterwards. Once service is back, confirm that important messages, invoices and orders have arrived.
The bigger lesson: you can't control Microsoft, but you can control your resilience
This is the second major Microsoft 365 outage of 2026. In January, users across North America lost access for almost 10 hours. In August, thousands of Outlook users worldwide were locked out. Outages like these aren’t rare events anymore. They’re something every business needs a plan for.
Microsoft keeps its platform running, but under its shared responsibility model, your data and your business continuity are your responsibility. Here’s what a resilient setup looks like:
- A written business continuity plan. Who gets told, how do staff communicate, and which tasks can carry on offline? Decide before the outage, not during it.
- Independent Microsoft 365 backup. Native retention isn’t a backup. A third-party backup of email, OneDrive, SharePoint and Teams means your data is always recoverable, whatever happens at Microsoft.
- A second way to communicate. A phone system or messaging channel that doesn’t depend entirely on Microsoft 365 keeps you reachable.
- Proactive monitoring. A managed IT provider watching service health 24/7 can warn your team early and tell them what to do, instead of leaving them guessing.
- Security awareness. Every big outage brings a wave of phishing. Staff who know what to look for are your best defence.
How Total Group helps
At Total Group, we’ve supported businesses across Hertfordshire, London and the Home Counties for over 25 years. During incidents like this, our clients don’t have to work it out alone. We monitor Microsoft 365 service health around the clock, keep teams updated, and handle the clean-up once services return.
Our Microsoft 365 services cover management, security and independent backup. Our backup and disaster recovery service makes sure your data and your operations can recover quickly. And with Cyber Essentials Plus and ISO 27001 certification, our cyber security team helps keep outage-themed phishing out of your inbox.
Don't wait for the next outage
The businesses that coped best this week already had a plan. If yours didn’t, now’s the time. Book a free, no-obligation review of your Microsoft 365 resilience, or call us on 01727 881 224. We’ll show you where the gaps are and how to close them, with no jargon and no surprises.
