On Thursday 12 November, a major Microsoft 365 outage cut organisations around the world off from their email, with disruption running from Thursday evening into Friday. Outlook, Teams and SharePoint were all affected, and for many UK businesses the working day simply stopped.
The cloud is reliable, but it is not infallible. Below we cover what happened, the scam risk that always follows outages like this, and five practical steps that will keep your business working next time.
What happened
The trouble started in the Americas on Thursday afternoon, when Microsoft reported that users could not reach their Exchange Online mailboxes. Within hours it confirmed the problem could affect users in any region. In the UK, outage reports surged from around 6pm and were still coming in at 3am on Friday.
Because so much of Microsoft 365 relies on Exchange Online, the impact spread well beyond email. Outlook, Teams, SharePoint, Copilot and Defender were all listed as affected, along with some Power BI, Purview and Windows 365 features. Government agencies in Australia, India and Japan were among those hit.
Microsoft says a process on its servers that handles secure connections became overwhelmed, so the servers stopped responding. Servers it brought back online kept failing again once traffic returned, which is why recovery dragged on through the night. Microsoft has said there is no indication of a cyber attack and plans to publish a detailed report on the root cause.
At the time of writing on Friday 13 November, Microsoft had not yet confirmed a full recovery. Microsoft’s status page can be found here: https://status.cloud.microsoft/
Why it matters for your business
You can’t stop Microsoft having a bad day, but you can control how much it costs you. Most SMEs and public sector teams now run email, calendars, calls, chat and shared files on one platform. That is efficient, but it means a single fault can stop everything at once.
When Outlook and Teams go down together, the costs add up quickly:
- Customers and suppliers can’t reach you, and you may not know they have tried
- Meetings and appointments are missed because calendars won’t load
- Staff lose hours trying to fix their own devices when the problem sits with Microsoft
- Quotes, orders and urgent decisions stall until service returns
Organisations with a plan already in place are the ones that keep working through days like this.
The real risk starts after the outage
Widely reported outages are a gift to cyber criminals, because everyone is expecting messages from Microsoft. Banks warned customers this week that scammers may use the disruption to target individuals and businesses. Expect phishing emails posing as service restoration notices that ask users to sign in again, plus fake IT support calls.
Make sure your team knows three simple rules:
- Microsoft will not ask you to reset your password because of an outage.
- Microsoft will not phone you to fix your mailbox.
- If an email or call feels wrong, don’t click and don’t share anything. Check with your IT provider first.
Five steps to keep working next time
- Agree a backup way to communicate. Decide now how staff, customers and suppliers will reach you if email and Teams are down. A business phone system that runs independently of Microsoft 365 is the simplest safety net. Write the plan down and share it.
- Back up your Microsoft 365 data independently. Microsoft keeps the service running, but protecting your emails, files and Teams data is your responsibility. An independent backup keeps critical information recoverable, whatever happens.
- Know where to find reliable updates. Bookmark Service health in the Microsoft 365 admin centre, status.cloud.microsoft and the @MSFT365Status account on X. A quick check stops your team chasing problems that aren’t theirs to fix.
- Don’t try to fix it yourself. Resetting passwords, rebuilding Outlook profiles or changing settings can’t solve a fault on Microsoft’s side. It usually just creates extra work once service returns.
- Train your team to spot scams. Short, regular awareness sessions turn your staff into your first line of defence, so opportunistic phishing never lands.
How Disking IT can help
Disking IT helps SMEs and public sector organisations across Hampshire and Surrey stay productive when the unexpected happens. We can put independent backup, continuity planning and staff awareness training in place for you, and monitor your systems proactively so you hear about problems from us first.
Book a free resilience check. We’ll review how your organisation would cope with an outage like this one and give you a short, practical action plan. No jargon, no obligation.
Call us on 0333 038 9070 or visit diskingit.co.uk to book yours.
