- Organizations turned to paper documents and fax machines as Outlook and other Microsoft 365 services experienced disruptions
- Microsoft said recovery efforts were progressing but some users could continue facing intermittent problems
A major global outage at Microsoft disrupted email, workplace communications and other cloud-based services Thursday, affecting businesses, government agencies and public services across the world and exposing how heavily everyday operations depend on the US technology giant.
The disruption began Thursday and continued into Friday.
It hit Microsoft 365, the company’s subscription package of workplace tools, which includes the Outlook email service, the Teams messaging and meeting app, the SharePoint and OneDrive file storage services, and the Copilot AI assistant.
The core of the problem was Exchange Online, the system that runs email and calendars for business Outlook accounts. Microsoft said all services that depend on it were affected, while those that do not need it kept working.
Within about an hour, outage tracker Downdetector received reports from users in 74 countries and territories. Reports of Outlook problems peaked at about 130,000 in the US.
Why it happened
Microsoft said a number of its servers unexpectedly stopped working, putting heavy pressure on the rest of its system.
The company said servers it brought back online kept failing again once traffic returned. It said it was also reversing a recent network configuration change that coincided with the start of the problem.
Charles Lamanna, a Microsoft executive vice president, said there was no sign the outage was caused by a cyberattack.
On Friday, Microsoft reported progress in restoring services in the Asia-Pacific region, Europe and North America, saying mailbox access and email delivery were improving, though some users could still face intermittent problems.
Courts, police and governments
In Japan, Deputy Chief Cabinet Secretary Masanao Ozaki said Friday that the outage had disrupted the government's shared IT infrastructure, preventing employees from accessing Outlook and other Microsoft services.
Government employees resorted to using paper documents to continue their work, according to Japan's Jiji Press.
Singapore’s Government Technology Agency said government email was down.
The Philippines’ Supreme Court said the outage had disrupted the judiciary’s digital services, warning of possible delays in email responses and other transactions.
In Australia, the outage cut live video feeds from courts, and schools told parents to phone in student absences instead of emailing.
The outage also affected the Australian Federal Police and domestic intelligence agency ASIO, according to local media reports.
In the US, city governments including Miami Beach, Austin and Jacksonville reported email problems and asked residents to call instead, while saying emergency services were still running, according to CNN.
In Colorado, the Arapahoe County Sheriff’s Office said its jail could not process online bail payments because staff were not receiving the necessary email notifications, so families had to pay in person.
In Britain, local authorities across Scotland reported widespread disruption to public services, including email and online payment systems, with some councils warning of increased pressure on telephone lines.
The Metropolitan Police is among several forces affected, warning that online crime reports may not reach officers, according to reports.
Hospitals and health services
Several National Health Service organizations in the UK asked patients and doctors to call rather than email.
The Lincolnshire Partnership NHS Foundation Trust asked for urgent referrals to be made by phone, while NHS Fife said patient services were continuing.
Australian Medical Association President Dr. Michael Bonning told The Guardian that some healthcare facilities had reverted to paper prescriptions because accessing electronic prescribing software required multifactor authentication involving Microsoft email services.
Banks and businesses
The disruption also reached the artificial intelligence industry, with ChatGPT maker OpenAI and Claude developer Anthropic reporting problems with tools that connect their AI services to Microsoft 365.
In Hong Kong, bankers at Morgan Stanley and Goldman Sachs told CNN they could not use email or Teams for hours.
In Japan, some banks and securities firms confirmed transactions by fax, local media reported.
Japanese logistics company Sagawa Express suspended online bookings for its luggage storage services at train stations and airports, directing customers to make reservations in person, local media reported.
In the US, truck maker Workhorse postponed its quarterly earnings call to Nov. 16.
Transport and travel
In Britain, National Rail warned passengers that the outage could prevent them from accessing train tickets sent by email, advising them to retrieve their tickets through railway websites or apps before traveling.
Indian airlines IndiGo and Akasa Air reported disruptions to their email-based customer support services.
