Engineers made gradual progress restoring Microsoft 365 on Friday after a server configuration update disrupted email and workplace systems worldwide.
Microsoft began restoring core workplace services on Friday after a server configuration problem caused an outage that lasted more than 19 hours, disrupting email, calendars and messaging tools for organizations across the world. The Guardian reported that the incident started around 6 p.m. GMT on Thursday and affected millions of users across government departments, businesses, schools and healthcare systems.
The disruption built on a major server failure that knocked out Microsoft 365 services across the world, leaving public agencies and private employers searching for alternative ways to communicate.
What caused the server failures
Microsoft indicated that the problem began with a configuration update that overloaded certain servers and knocked them offline. When traffic shifted toward the remaining active hardware, those systems were overwhelmed as well. The company then tried to apply a fix, but servers that restarted became unresponsive again as traffic rushed back in.
Engineers responded by restricting traffic to affected servers in targeted areas and reverting some machines to an earlier software configuration. BBC News reported that Microsoft acknowledged the initial remedies were “not taking as expected” because of the severe strain placed on its network infrastructure.
Both Microsoft and outside cybersecurity specialists dismissed suggestions that the breakdown resulted from a cyberattack. The company also found no evidence that artificial intelligence caused the issue, despite recent security incidents elsewhere.
Where the disruption hit hardest
In the United Kingdom, the incident created significant communication problems for primary healthcare and law enforcement. Multiple police departments, including the Metropolitan Police, Greater Manchester Police, North Yorkshire Police, South Wales Police and Dyfed-Powys Police, reported that their online reporting forms were affected and asked the public to call 101 for non-emergency matters. The National Pharmacy Association said communication between pharmacies and family doctors was disrupted, which could lead to prescription delays and longer wait times for patients.
GP surgeries in Hampshire and Shropshire instructed patients to call or walk into clinics directly, while a clinic in Penzance reported receiving zero emails during the working day. The National Health Service, which holds a five-year contract for Microsoft 365 in England, confirmed service disruptions. In contrast, Heathrow, Stansted and Manchester airports operated normally, the London Ambulance Service did not rely on Microsoft for critical systems, and UK intelligence agencies ran secret work on separate infrastructure.
Disruptions spread across several other countries. In the United States, issues were reported by the US House of Representatives, a court in Maine, and municipal offices in Colorado and Florida. In Australia, government agencies, courts, schools and an intelligence agency encountered problems accessing inboxes. Public offices in France, Belgium, Germany and the Netherlands logged technical difficulties, with one French municipality asking residents to communicate by telephone.
In Japan, some private companies turned back to fax machines to manage communication. The shipping firm Sagawa Express could not process online bookings at select train stations and airports, while drugmaker Taisho took customer orders over the phone. Indian carriers IndiGo and Akasa Air reported disruptions to email support, and Taiwanese financial firms suffered interruptions to fund management tools.
What happens next
By Friday morning, Microsoft had restored Teams chats and meetings, narrowing most of the remaining downtime to its Microsoft Exchange email service. By midday UK time, the company reported “encouraging recovery progress in Europe”, along with stabilizing conditions in Japan and continued progress across North America and the Asia Pacific region.
UK Defence Minister Luke Pollard said the government is assessing the impact across its departments and will issue a formal statement once that evaluation wraps up.
