For the latest, see this update from Computer Business Review

Microsoft has confirmed a widespread Office 365 outage this morning.

At the time of writing it had yet to update its public-facing status page, which showed normal service, but an update for administrators blamed a “subset of mailbox database infrastructure [that] became degraded, causing impact.”

At 1.54pm it changed that attribution, with Microsoft 365’s status account on Twitter instead saying “a subset of Domain Controller infrastructure is unresponsive, resulting in user connection time outs” and pledging mitigation.

No further updates resulted in the following five hours. Users around the world, from photographers in Turkey to accountancy practices in the UK, took to social media to urge immediate action as business faltered in the absence of connectivity.

It remained unclear the incident didn’t result in fail-over to another server/cluster. Computer Business Review has asked Microsoft the question.

Service interruptions appear to have begun around 8:00am for some users. Organisations across the UK and the Netherlands are among those reporting issues with Exchange Online.

Microsoft Office 365 Down: Users Globally Affected

A Reddit thread on the latest outage also shows users affected in South Africa, Iceland, Switzerland and South America as well. Buggy code updates have been blamed for previous similar interruptions to Office 365 service.

Pete Banham, a cyber resilience expert at Mimecast, commented in an emailed statement: “Email downtime should not be the new normal. This is the ultimately human error rather than technical failure. IT leaders need to wake up to their responsibility here. It’s clear that relying on any single cloud provider will continue to create business disruption every time there’s an outage.”

The outage is the latest to frustrate European users.

An overloaded Redis cache was blamed for a batch of Azure and Office 365 outages for MFA users in late November.

See also: Redis Overload to Blame for 17-Hour Azure MFA Login Crisis