Microsoft has restored services across its Microsoft 365 platform following a global outage that disrupted access to Outlook, Teams, Word, Excel, PowerPoint, OneDrive, SharePoint and its Copilot artificial intelligence assistant.

The technology company announced on Saturday, November 14, that it had resolved the underlying technical problem and restored services to customers and regions that were still experiencing disruptions.

“We have completed our efforts to address the underlying issue of the incident and restored service to the remaining impacted customers and regions,” Microsoft said in an update.

The outage, which began on Thursday, November 12, affected users in at least 74 countries and territories, according to reports from Downdetector, an online service that tracks disruptions to digital platforms.

The disruption affected businesses, government agencies, financial institutions, healthcare providers, schools and other organisations that depend on Microsoft’s services for communication and daily operations.

Microsoft apologised to affected customers, acknowledging the disruption caused by the incident and promising to address the underlying technical problems.

Microsoft attributed the outage to a technical problem associated with an earlier network capacity upgrade that surfaced following a subsequent network change.

The company said some servers became unexpectedly unavailable, affecting access to services connected to Exchange Online, the infrastructure supporting Outlook and other Microsoft 365 applications.

Microsoft ruled out a cyberattack or malicious activity, saying the incident was not related to cybersecurity threats or artificial intelligence agents.

Engineers worked to restore the affected infrastructure, but the recovery process was gradual as the company carried out checks to ensure that services could operate reliably without further disruptions.

The outage lasted more than 24 hours before Microsoft confirmed that all affected services had been restored.

The disruption exposed the extent to which businesses and public institutions depend on Microsoft’s cloud-based applications.

In the United Kingdom, some healthcare facilities experienced difficulties accessing digital systems, while police forces reported problems with online crime-reporting services.

Some hospitals and healthcare workers had to rely on alternative arrangements, including paper records, while schools and other organisations experienced difficulties communicating with parents and staff.

Financial institutions and businesses in parts of Asia also reported disruptions. Some organisations resorted to telephone calls and alternative communication channels to maintain operations.

The outage also affected connections used by artificial intelligence companies OpenAI and Anthropic to interact with Microsoft 365 services.

Microsoft said more than 430 million people use its Microsoft 365 applications, highlighting the potential impact of disruptions to its infrastructure.

The incident has renewed concerns about the risks of relying heavily on a small number of technology providers for essential business and public services.

Although cloud-based platforms offer organisations flexibility, accessibility and reduced infrastructure costs, widespread dependence on a single provider can expose millions of users to simultaneous disruptions when technical problems occur.

Technology experts have consequently stressed the importance of backup systems, alternative communication channels and business continuity arrangements.

For organisations that rely on Outlook, Teams and other Microsoft applications for daily operations, the latest incident serves as a reminder that digital resilience requires more than access to cloud services.

Microsoft has indicated that further updates on the incident will be available through its Microsoft 365 administration centre under incident reference MO1550821.

The company has not yet published a full technical post-incident report detailing every stage of the failure and recovery process.