Microsoft Outlook Web Outage Disrupts User Access Due to Code Change

On March 19, 2025, Microsoft experienced a significant Outlook web outage that disrupted user access across its cloud-based email services.

The root cause was a flawed code change implemented during a recent software update.

What Happened During the Outage

The disruption began early Wednesday afternoon. Users reported login issues, connection errors, and trouble accessing the Outlook website.

Downdetector logged thousands of complaints shortly after the issue surfaced, confirming widespread impact.

Microsoft’s Swift Response

The Microsoft 365 Status team acknowledged the outage and began investigating under the incident ID EX1036356.

They advised IT administrators and users to monitor the admin center for updates.

Root Cause and Fix

Engineers traced the issue to a recent code update that caused errors in Outlook on the web.

To resolve the issue, Microsoft initiated a rollback of the faulty code and monitored the system for stability.

Outlook Restored After Hours of Downtime

After several hours, Microsoft confirmed that the rollback had resolved the issue for all users.

Normal service resumed, and users were directed to the admin center for detailed information.

Recent Trend of Microsoft 365 Outages

This incident follows earlier disruptions in March caused by similar code changes.

These repeated issues highlight the complexity of updates in large-scale cloud systems.

Lessons for IT Teams

The outage emphasizes the importance of robust testing and rollback protocols.

IT administrators should ensure contingency plans are in place to handle such disruptions.

Microsoft’s Ongoing Commitment

Microsoft has reaffirmed its commitment to service reliability and fast issue resolution.

The company aims to minimize future disruptions while enhancing user experience on its platforms.

https://grctechinsight.com/2025/03/20/microsoft-outlook-web-outage-disrupts-user-access-due-to-code-change/