Global Outlook Outage: What Happened on March 1, 2025?

On March 1, 2025, a global Outlook outage disrupted email access for millions of Microsoft users worldwide.

This widespread O365 outage impacted not only Outlook but also other key Microsoft 365 services, such as the Office business suite, Teams, and even the Microsoft Store.

The issue first became apparent on Saturday, which coincided with the start of a new month, when many users checked their payday emails.

Furthermore, as March marks the end of the current Financial Year (2024-25) many important business communications were directly affected.

So naturally many concerned users turned to platforms like Down Detector to report their Outlook down status and determine the scope of the MS Outlook outage.

This blog explains what caused this significant disruption to Microsoft’s email service and, more importantly, how to safeguard your data against similar incidents in the future.

Let us go over the chronology of the issue when it started and how it played out.

Timeline and the Immediate Impact of Outlook Disruption

The incident began on Saturday evening for people living in the western hemisphere. Discussions on the issue started to appear on public forums and the topic started to trend on X.com around 8:40 PM Eastern Time. By 9:15 PM, there were more than 9000, on outage tracking sites like Down Detector.

The main concentration of users complaining about the issue was from big business cities like London, Manchester, and many regions of North America.

Many users were not even able to log in let alone attempt other tasks like converting Outlook web emails to PDF through the portal. Moreover, even the official desktop-based Microsoft email clients were also unable to process new emails.

Even the mobile app (both iOS/Android versions) faced a similar outage. Some personal anecdotes on social media discussions indicated that this problem also affected legacy Hotmail accounts. Moreover, it also led to disruptions within third-party email clients that rely on Microsoft’s infrastructure so no one was immune from this issue. However, users were still unsure as to why this issue occurred in the first place.

What Caused the Global Outlook Outage?

Microsoft did its investigation on the issue and soon revealed that there had been an issue with a recent code update. That was the root cause of the service disruption.

The official statement from the company consisted of the words “problematic code change” next to the trigger.

Apart from this announcement, no other specific details were made public by Microsoft on any of its social media handles or the official service status page. Admins were asked to check the MO1020913 incident reference number or visit any one of the following pages:

https://admin.microsoft.com/servicestatus

https://portal.office.com/ServiceStatus

Microsoft confirmed that they reverted the code update at approximately 10:00 PM ET.

Within an hour or so M365 services impacted by the error including Outlook gradually resumed normal operations. So users were once again free to share calendars in Outlook 365 and perform other business and personal tasks

Like the issue itself, rollback also affected all platforms, impacting users of desktop clients (both new and classic), mobile apps, and integrated third-party clients.

However, this disruption once again reiterated the importance of maintaining an offline copy of email data.

How do Backups Allow Organizations to Maintain Data Access During a Global Outlook Outage?

Incidents like this are not new nor are they going to stop any time soon. That is why organizations need robust data protection strategies.

Although this time there was only a service outage that too because of Microsoft’s internal code it serves as a warning against more serious events.

Any major ransomware-style attack may lead to a longer service downtime and in the worst-case scenario may cause a permanent data loss event.

So admins must consult with other decision-makers in their organizations to set up a preemptive backup strategy. Which would allow for the following.

• Allows Business Continuity: Local data backups are readily available for information retrieval when the cloud-based systems face outages.
• Disaster Recovery Ability: Backups are kept isolated from outside connections so even when there are global Outlook outages, cyber-attacks, or accidental deletions admins can still access the required data.
• Maintain Compliance Requirements: Sometimes legal requirements force your organization to maintain an off-site backup.

All of this means backups are important but begs the question of how to form the said backups.

Use Professional Backup Solution to Beat Future Outlook Service Downtimes

The SysTools Backup for Microsoft Office 365 is a perfect solution to build secondary copies of your M365 cloud data.