On 25 January 2023 Microsoft made a wide-area network router change that caused packet forwarding problems across its backbone. Teams, Exchange Online, SharePoint, OneDrive and the admin portals became unreachable or badly degraded for several hours, right across the European working day.
Why this one is worth remembering
It is the clearest example of concentration risk in a normal small-business setup. Email, chat, files and phone system all live inside one vendor. That's efficient and usually reliable — Microsoft's uptime is far better than most on-premise servers ever were — but it means one bad change removes every way of communicating at the same time.
Sensible mitigations
- A second way to reach your team. A WhatsApp group or a phone list costs nothing and works when Teams doesn't.
- A second way for customers to reach you. A hosted phone system on a different provider keeps you contactable when email is down.
- Independent email continuity or archiving if email really is the business. Some mail-filtering products can spool and let you read mail during an outage.
- Local copies of what you need today. OneDrive Known Folder Move keeps a synced copy on the laptop, so people can keep working on documents even when the cloud isn't there.
We watch the Microsoft 365 service health feed for the tenants we manage and will tell you when a problem is Microsoft's rather than yours.