Microsoft 365 outage (12–13 November 2026): what UK and Irish businesses need to know

If you’ve had trouble with Outlook, Teams or other Microsoft 365 apps since Thursday, you’re not alone. Microsoft is dealing with a global service disruption,...

Gina Brennan

Published Date: 13/11/2026

If you’ve had trouble with Outlook, Teams or other Microsoft 365 apps since Thursday, you’re not alone. Microsoft is dealing with a global service disruption, and businesses across the UK and Ireland are feeling the effects, including many of our own customers. At the time of writing on Friday 13 November, Microsoft is still restoring service.

This is a Microsoft-wide issue. It is not caused by your account, your devices or your setup, and there’s nothing you need to fix on your side. Below, we explain what happened, what you can expect and how we’re supporting you.

Need help now? Call our team on 03330 156 651 (UK) or 01263 5299 (IE).

What happened

The disruption began late on Thursday afternoon, 12 November (UK and Irish time), and continued into Friday 13 November. Businesses in the UK, Ireland and around the world found they couldn’t send or receive emails, open their inboxes or load some Microsoft apps.

Microsoft lists these services as affected:

Outlook and Exchange Online (email)
Microsoft Teams
SharePoint and OneDrive
Microsoft 365 Copilot
Microsoft Defender XDR

According to Microsoft, a process on some of its servers that handles secure connections became overwhelmed. Those servers stopped responding, which put extra strain on the rest of its infrastructure.

Was this a cyber attack?

No. Microsoft has confirmed there is no indication of a cyber attack or malicious activity behind the outage. This is a technical fault in Microsoft’s own infrastructure, not a security breach.

You don’t need to reset your password or change any settings because of this outage.

What you can expect

Microsoft has found a way to bring affected servers back online safely and is rolling it out across its systems. Partial recovery has been reported in several regions, though it isn’t yet consistent.

Recovery is happening gradually rather than all at once, so you may notice:

Some services working normally while others are still slow or unavailable
Emails arriving late as delayed messages catch up
Apps that work one moment and drop out the next

Microsoft hasn’t yet given a time for full recovery. Microsoft posts its latest updates on the Microsoft 365 Status account on X (@MSFT365Status).

What you can do in the meantime

Pick up the phone. For anything time-sensitive, a call is the most reliable way to reach customers and colleagues right now.
Try the web or mobile apps. If the desktop app isn’t loading, Outlook on the web or the mobile app may work, and the other way round.
Avoid repeated troubleshooting. Reinstalling Office or resetting devices won’t help, as the fault is on Microsoft’s side.
Be alert to scams. Outages are a common moment for phishing emails pretending to be from Microsoft or IT support. Don’t click links asking you to sign in again or “restore” your mailbox. If in doubt, call us before you act.

Building resilience for next time

Outages like this are a reminder that no single platform should be the only way your business communicates. Here’s how the services we provide across the UK and Ireland can keep you working.

Microsoft 365 through Yellowcom. If we manage your Microsoft 365, our team is tracking Microsoft’s service health for you, so you don’t have to chase updates or troubleshoot yourself.
Cloud phone systems. Calls on a Yellowcom cloud phone system such as iPECS don’t rely on Microsoft 365, so your phone lines can keep running while email and Teams are disrupted. If you use Microsoft Teams as your phone system, talk to us about diverting calls to mobiles as a backup.
Business mobiles. A business mobile plan on a leading network gives your team a direct way to call and text customers when desktop apps are down.
Cybersecurity and email security. Scammers often take advantage of outages. Our managed email security and cybersecurity training help your team spot fake “Microsoft” messages before anyone clicks.
Managed IT support. Our managed IT customers have helpdesk support and monitoring in place, so we can help prioritise what matters to your business while services recover.

Once things settle, it’s a good time to review how resilient your setup is. Our free IT Health Scorecard takes less than two minutes and highlights where your business may be exposed.

How we’re supporting you

Microsoft 365 is down, but our phones aren’t. Our local support teams in Belfast, Glasgow and Dublin are monitoring Microsoft’s updates closely and are on hand if you have questions or need help.

Email and Teams messages to us may be delayed, so please call us directly: