Microsoft is exploring alternative solutions to restore its Outlook email service after efforts to fix a major global outage failed to produce the expected results, leaving users, businesses and government agencies unable to access key Microsoft 365 services.

The disruption, which lasted for several hours on Thursday, also affected Microsoft Teams and its Copilot artificial intelligence assistant. The company said the problem was linked to unusually high demand on parts of its infrastructure across multiple regions, resulting in connectivity failures for users.

Microsoft said attempts to improve the affected systems had not worked as anticipated and that engineers were looking for other ways to increase capacity. “We’ve monitored the status of the changes applied to improve serviceability and confirmed they’re not taking as expected,” the company said in an update on X.

The outage reportedly spread to 74 countries and territories within an hour, according to outage-tracking platform Downdetector. Users across the Americas, Europe, Asia and Africa reported difficulties accessing Microsoft services. New Zealand’s foreign ministry also said the disruption had affected its ability to receive emails, including communications at its embassies, consulates and representative offices worldwide.

Microsoft initially said it was investigating reports from the Americas but later confirmed that Microsoft 365 connectivity problems could affect users in any region. The company said it was working to reduce the impact and later reported limited recovery as it attempted to redirect traffic away from affected servers, warning that service would return gradually as capacity was restored.