“In case of emergency, we would appreciate it if you would contact the relevant department by phone or fax,” the Digital Strategy Division of the southwestern city of Kumamoto stated, as a global outage of Microsoft (NASDAQ: MSFT) software disabled municipal email systems on Friday.
The tech disruption lasted more than 20 hours, stretching from Thursday until Friday, and hit millions of users of Microsoft 365 worldwide, as reported by BBC. In Japan, the failure forced local governments and corporate offices to rely on analog fax machines and telephone lines to maintain operations.
Operational Impact on Government Infrastructure
The outage disabled Microsoft Outlook, Teams, and the Copilot AI assistant, leaving offices unable to send or receive messages. According to La Vanguardia, the failure also crippled the Government Information System, known as GSS, which centralizes computers and networks across Japanese ministries and agencies.
The matter reached the Lower House of the Diet, the Japanese Parliament. “We were supposed to communicate with you today via email, but that service is not currently available… So, instead, I will send it by fax,” politician Akira Nagatsuma told the Cabinet Committee, according to Asahi television, prompting loud laughter in the chamber.
“We have confirmed that the GSS, the infrastructure of the Government Information System, is also experiencing an outage,” said Masanao Ozaki, Japan’s Deputy Chief Cabinet Secretary, without specifying the exact number of public offices affected.
Other municipalities also activated contingency measures. The northeastern city of Joetsu urged departments to use fax machines for urgent matters to prevent operational stoppages during the outage. The company has apologized for the inconvenience caused.
Microsoft attributed the disruption to high loads on its infrastructure rather than a cybersecurity incident. Charles Lamanna, a senior executive at Microsoft, confirmed that the issue stemmed from technical difficulties rather than an attack.
Sam Mubb stated: “Microsoft has confirmed that it is a technical failure, not a cyberattack.” Microsoft Chief Executive Officer Satya Nadella and the tech giant have ruled out any indications of a cyberattack for the time being.
Precedent for Analog Fallbacks in Japanese Offices
Despite ongoing modernization efforts by authorities, analog fax machines remain embedded in Japanese administrative routines. More than 70% of the country’s public schools and institutes used fax machines at the end of 2025, according to a survey cited by the Asahi newspaper.
This is not the first time technical failures have forced Japanese entities back to paper-based communication. Last year, beverage manufacturer Asahi Group Holdings was compelled to log shipments exclusively by phone and fax following a cyberattack that hit local infrastructure.
We regret that today’s outages caused disruptions for our customers, and we are working to address the issue. We will continue to share more information as soon as we have it, and for now I can confirm that there is no indication this is the result of malicious or cyber activity.
Ubiquitous convenience stores, known locally as konbini, also provide fax services to the public, offering an immediate fallback when digital networks fail.
| Service / Entity | Impact Reported | Contingency Used |
|---|---|---|
| Microsoft 365 | Global outage lasting over 20 hours | Phone and Fax |
| Kumamoto Digital Strategy Division | Email and internal platforms down | Analog Fax |
| Japanese Government GSS Network | Centralized ministry computers disrupted | Alternative messaging and fax |
Normal operations resumed gradually on Saturday as Microsoft implemented fixes across affected regions in the Americas, Europe, and Asia-Pacific. Technicians encountered machines stuck in defective states that hindered synchronization, delaying full recovery efforts.
