Microsoft Blames ‘Problematic Code Change’ for Recent Microsoft 365 Outage
Microsoft 365 services suffered a major outage over the weekend due to a faulty code change.
Published: Mar 04, 2025
Key Takeaways:
- Microsoft confirmed that a faulty code change caused a widespread outage.
- This issue prevented thousands of users from accessing services like Outlook, Teams, and Exchange.
- Microsoft identified the issue, reversed the problematic code, and restored services.
This weekend, Microsoft tackled a major outage that left thousands of users unable to access key Microsoft 365 services like Outlook and Teams. The company later confirmed that a faulty code change was to blame for the disruption.
What caused the Microsoft 365 outage?
According to Downdetector, the outage began at around 4:00 PM ET on March 1, disrupting key services like Microsoft Outlook, Teams, Exchange, Microsoft 365, and Azure. At least 30,000 Outlook users, 24,000 Office 365 users, and 150 Microsoft Teams users were affected. Reports indicate that the majority of impacted customers were in U.S. cities, including New York, Chicago, and Los Angeles.
Microsoft identified a potential cause of the outage and reported that Microsoft 365 services were starting to recover. By 7 PM ET, the company confirmed that the issue was resolved by rolling back a faulty code change.
“We’ve identified a potential cause of impact and have reverted the suspected code to alleviate impact. We’re monitoring telemetry to confirm recovery,” Microsoft explained. “Following our reversion of the problematic code change, we’ve monitored service telemetry and worked with previously impacted users to confirm that service is restored.
Microsoft 365 faces more downtime and login issues
However, some iOS users continued to face issues logging into their Microsoft 365 accounts. Despite the fix, these users had to delete and then reinstall the app on their devices to restore access.
On Monday, Microsoft faced another issue with Microsoft 365 services, causing downtime for many customers. This affected various services, including Microsoft Teams, which disrupted for some users. The impact varied, with some people able to access Microsoft 365 services while others couldn’t.
Unfortunately, Microsoft has a history of major outages, and January 2025 was no exception. A networking configuration change in the East US 2 region caused widespread Azure service disruptions, leading to timeouts, connection drops, and resource allocation failures. The outage affected key services like Virtual Machines, Azure Databricks, and Azure Container Apps. Microsoft ultimately resolved the issue by rolling back the faulty configuration.