Businesses and public services worldwide are facing disruption after a major Microsoft outage left organisations struggling to access emails, manage customer communications, and use essential workplace systems.
The disruption, which began on Thursday, 12 November, has continued into Friday morning, affecting companies, government departments, and other organisations dependent on Microsoft’s cloud-based services.
US commercial vehicle manufacturer Workhorse Group postponed its third-quarter earnings conference call from 12 November to 16 November, explicitly citing the outage. In India, airlines IndiGo and Akasa Air reported interruptions to their email support services, directing customers towards alternative contact channels.
Government operations have also been affected. Australian police, security agencies, schools, and public administration systems reported problems, while Japan’s government acknowledged disruption to its IT infrastructure. The US House of Representatives also confirmed that its users had been affected.
The scale of the incident has raised fresh concerns about the concentration of essential business operations within a relatively small number of technology platforms.
Microsoft 365 provides the email, document management, collaboration, and productivity tools used by organisations across almost every sector. Disruption to those interconnected services can interrupt activities ranging from customer correspondence and meeting arrangements to internal approvals, reporting, and administration.
The outage also exposed dependencies beyond Microsoft’s own applications. OpenAI and Anthropic reported problems with services connecting their AI products to Microsoft 365, illustrating how failures in one technology provider can affect products delivered by others.
Disruption extends across global markets —
Reports of problems began escalating on Thursday evening, with monitoring service Downdetector recording more than 130,000 reports concerning Outlook in the United States at the peak. Those figures represent submitted reports rather than the total number of affected customers.
Problems were subsequently reported across Europe and Asia-Pacific, extending the disruption into Friday’s working day.
UK users also reported difficulties accessing Microsoft services on Thursday evening. However, the number of affected British businesses and the financial cost of the disruption have not yet been established.
The most significant problems have involved Outlook and Exchange Online, leaving some employees unable to access inboxes, send or receive emails, or use connected calendar functions.
Microsoft Teams, Copilot, SharePoint, and other Microsoft 365 services have also experienced problems, although the impact varies between applications. Core Teams messaging and meetings have remained largely functional, while features that depend on Exchange Online have been more directly affected.
The operational consequences are not necessarily confined to the period when systems are unavailable. Delayed correspondence, outstanding customer enquiries, and interrupted workflows can leave businesses with additional work once services resume.
Ashwin Pal, a risk advisory partner at RSM Australia, warned that smaller businesses could be particularly exposed because they often lack the resources and alternative systems available to larger organisations.
He also highlighted the cost of clearing backlogs once normal operations resume, although the overall financial impact of this outage remains uncertain.
Microsoft struggles to restore services —
Microsoft has been attempting to restore its infrastructure after identifying unexpectedly unavailable servers and increased pressure on the remaining systems.
Engineers found that a process responsible for establishing secure connections was becoming overwhelmed, causing affected servers to stop processing requests. Some systems initially recovered after restarts but became unresponsive again when traffic returned.
The company has been testing configuration changes, increasing capacity, and redirecting traffic. A recent network configuration change is also under investigation, but Microsoft has not confirmed a definitive root cause.
Initial recovery measures failed to produce sustained improvements. The company subsequently reported limited progress in some regions while continuing to work on a broader restoration.
Microsoft executive vice-president Charles Lamanna said there was no indication that the incident had been caused by malicious or cyber activity.
The incident follows an Azure cloud outage in October and adds to scrutiny of the resilience of technology infrastructure supporting everyday business operations.
With restoration still incomplete on Friday morning, affected organisations face continued uncertainty over when normal communications and connected workflows will resume.
