Microsoft 365 recovers with Outlook back online

Microsoft infrastructure and services have recovered after an 18-hour outage, with Outlook now accessible and the backlog of emails processing.

The cloud service provider said that it is “seeing encouraging recovery progress, with service availability and email delivery performance improving across a growing portion of affected Microsoft 365 infrastructure”, in a status update just past 11pm AEDT on Friday night.

iTnews was able to access Outlook for the first time all day, although scheduled emails sent during the day appeared hours out of order.

The breakthrough came at about 10pm AEDT, with Microsoft reporting success in its recovery efforts for “portions” of infrastructure in the Asia Pacific region.

It has also now reported gradual recovery in other regions, including the United States, which is just beginning its Friday.

"We’re seeing encouraging recovery progress in Europe, with service availability and email delivery performance improving across a growing portion of affected Microsoft 365 infrastructure," Microsoft said.

"Japan remains comparatively more stable, while North America is also improving; however, some users may still experience intermittent issues as recovery actions continue."

The vendor added that “reducing email queues and backlogs remains a priority.”

Microsoft has altered its typical email timeout window, extending it to 48 hours, “to help protect delayed messages as delivery catches up.”

Organisations across the world had a largely unproductive day, with many, such as internet providers and government departments, warning customers that they were unable to receive or action requests for assistance while Microsoft services remained inaccessible.

Australia activates agreement

Prioritisation of Asia Pacific for recovery may have been influenced by a "digital resilience" agreement that Microsoft has with the Australian federal government.

Australia's Home Affairs Minister Tony Burke indicated that the agreement had been activated.

"The relationship that we have with Microsoft is an important one," Burke said in televised remarks.

"When it came to the formal cyber agreements which I've signed on behalf of Australia, the first of those was with Microsoft.

"That agreement has, in fact, been activated today to make sure that we get appropriate prioritisation of Australian interests in this."

'No evidence of malicious activity'

Microsoft has not yet disclosed the cause of the outage, one of its worst in recent memory, impacting users globally.

The company said that “at this time, we have no evidence of malicious activity associated with this incident.”

“We will continue to treat this with urgency until full mitigation, and we will share a full post-incident report with root cause and defense-in-depth actions after mitigation is complete,” it said.

Burke said that the Australian government was getting briefed by the National Cyber Security Coordinator, Lieutenant General Michelle McGuinness, and by Microsoft A/NZ president Jane Livesey.