Access to Outlook has been restored for some users in parts of the world and now Microsoft, the company that makes Outlook is apologising.
In a statement posted to several of the company's social media channels, the Washington state-based technology giant briefly explained what happened.
Hackers and other nefarious possibilities were ruled out.
"The incident was introduced by an issue during an earlier network capacity upgrade that surfaced following a recent network change," Microsoft's statement read in part.
"We have addressed the underlying issue and continue to restore service to remaining customers and regions," it added, promising to supply more of a detailed explanation as to what happened and why once the company's review was finished.
Microsoft also shed light on why this particular problem took so long to resolve.
"Given the scale of demand, we restored services gradually, validating stability at each stage. While this took longer, it helped ensure a stable restoration ... "We are deeply sorry for the disruption this incident has caused our customers and partners," the statment read.
Users began receiving emails again on their Outlook accounts starting at about 5.20pm local time, on both desktop and mobile versions of the app.
The restoration comes after Microsoft said on Friday that its email services were being restored in parts of the Asia Pacific region, after "broader improvements" were observed in North America and "sustained improvements" across much of Europe.
The US tech major, however, acknowledged that some users may continue to experience intermittent access issues or delayed email delivery "as mitigation progresses across the remaining affected infrastructure".
The disruption affected Outlook, Teams and the Copilot AI service for millions of people, companies and governments around the world on Thursday, and the issue continued into Friday.
"Traffic is being gradually restored and we're seeing improvements in key customer scenarios, including mailbox access and delayed email processing. However, some users may continue to experience intermittent issues," Microsoft said in an update.
Analysts have told The National that a continuing outage of Microsoft’s collaboration tools would have a “cascading” effect on businesses, with the financial impact increasing the longer it stretches.
On Friday, Microsoft stressed that it will continue to put efforts into a robust investigation as to what took place.
"We know the trust they place in our services and take that responsibility extremely seriously," the company said.
