Microsoft 365 outage: How to keep your business running when email goes down

On Thursday afternoon, 12 November, Outlook stopped working for businesses around the world. From around 16:00 UK time, people couldn’t open their mailboxes, and emails arrived hours late or not at all. Within an hour, users in 74 countries and territories had reported problems, and Outlook reports on Downdetector peaked at nearly 140,000 around 18:00 GMT.

By Friday the outage had stretched into a second day. Microsoft says services are now being gradually restored, but warns that some intermittent issues may continue.

What happened

The outage started in Exchange Online, the service behind Outlook, and spread to the tools that depend on it:

• Outlook: mailboxes wouldn’t load, and incoming mail was delayed. Microsoft extended its email timeout window to 48 hours so that delayed messages wouldn’t be lost.
• Calendars and files: some users couldn’t see calendar details or open certain files.
• Copilot: Microsoft’s AI assistant couldn’t work properly, and AI tools from other companies that connect to Microsoft services ran into problems too.
• Teams: chat and online meetings mostly kept working, but anything tied to email and calendars was affected.

Microsoft said a number of servers became unexpectedly unavailable, which overloaded the rest, and that there is no sign of a cyberattack. It also warned that services that had come back could become unresponsive again, in any region.

Who it hit

The disruption reached far beyond office workers checking their inbox. According to CNN’s live coverage, banks, governments and courts in several countries were affected, and the US House of Representatives had its engineers working with Microsoft. City governments across the US asked residents to phone instead of emailing, and one sheriff’s office said bail payments were delayed. In the UK, a disruption to the NHS email system was expected to stop some patients from getting their prescriptions on time. One listed company even postponed its quarterly earnings call, citing the outage.

The real lesson: one provider, one point of failure

Outages happen to every cloud provider, and no platform is immune. The problem isn’t that Microsoft had a bad day. It’s that for many organisations, Microsoft is the day: email, calendar, meetings, files and AI assistants all sit on the same foundation. When that foundation fails, everything stops at once.

The question worth asking now is simple: if this happened again tomorrow, how would your team keep working?

How Google Workspace can help

Since Thursday, we’ve had organisations contacting us urgently about Google Workspace licences. Some want a backup so an outage like this can’t stop them again. Others are ready to move completely. Here’s how we help, depending on where you are:

• A backup for critical teams. Google Workspace runs alongside Microsoft 365. Leadership, customer service or operations can have working email, chat and video calls on Google even when Microsoft is down, without changing anything for the rest of the company.
• A planned move away from Microsoft. Google’s own migration tools move email, files and Teams chats cloud to cloud, without extra servers or third-party licences. Teams can keep working with Word, Excel and PowerPoint files during the transition.
• Licences without the hassle. As a Google Workspace Premier Partner, we supply licences directly and help you set them up properly from day one.

👉 One honest note: a company-wide switch doesn’t happen overnight. Rolling out thousands of accounts safely takes planning, even with the best tools. That’s why the best time to set up a backup is before the next outage, not during it.

To see what a move involves, start with Google’s free guide, Migrating your data to Google Workspace. Or talk to us directly: we’ll look at your setup and tell you honestly what’s realistic, and how fast.