Microsoft email service Outlook showed signs of resuming operations after an outage that stretched past the 20-hour mark, a duration considered extensive for enterprise communication platforms.
The technical failure triggered a snowball effect across the company’s server architecture as a surge of devices attempted to reconnect simultaneously, BBC News reported.
“What Microsoft has told us is that the part of its servers that sets up secure connections is getting swamped, and once that happens the server just stops answering,” said Prof James Ferryman from the University of Reading’s department of computer science.
Ferryman explained the mechanics behind the prolonged disruption to BBC News.
“The trouble is this kind of failure snowballs,” he said.
One server fails, its workload transfers to the next one, and huge numbers of phones and laptops keep trying to get back in.
“You can’t just turn it all back on at once. You have to bring it back bit by bit,” Ferryman told BBC News.
Consequently, resolving the issue involves handling the massive wave of gadgets attempting to link back up as services become operational again, alongside fixing the actual bug.
Gergely Orosz, who previously worked as a top software developer at prominent technology firms like Uber and Skype, said that this event might qualify as the “most disruptive of all time”.
Orosz said that while measuring the exact headcount of affected users remains difficult, he “cannot recall” an outage over business email ever taking this long to return to normal.
Australian cyber-security expert Troy Hunt told BBC News that the outage could have far-reaching consequences.
“Microsoft is a massive part of the internet backbone and reminds us how critical email still is. “In addition to hindering employment duties for numerous individuals, he said that the disruption impacts tasks such as discussing appointments, completing purchases requiring verification, and establishing or logging into accounts and services.”
In a statement, Microsoft said it was “deeply sorry for the disruption this incident has caused our customers and partners. “We know the trust they place in our services and take that responsibility extremely seriously. We are seeing broad recovery and stability across our services.”
