No clear reason identified for mass Microsoft outage

Questions remain about what may have caused a global outage to Microsoft services like Outlook - with still no long-term fix nearly 12 hours on.

At least 74 countries have been impacted, including New Zealand, Australia, the UK, and US.

Microsoft says it's now seeing partial recovery across some regions - but it's not sustained. 

Agencies like Health New Zealand have been working to minimise the disruption.

Microsoft's former National Technology Officer Russell Craig told Heather du Plessis-Allan the company's operations are extremely complex, so it's easy for things to go wrong.

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