Outage in Microsoft Office 365

Potential issues accessing Outlook mailboxes through one or more connection methods

Resolved Major
September 30, 2025 - Started 4 days ago - Lasted about 4 hours

Need to monitor Microsoft Office 365 outages?
Stay on top of outages with IsDown. Monitor the official status pages of all your vendors, SaaS, and tools, including Microsoft Office 365, and never miss an outage again.
Start Free Trial

Outage Details

We're continuing to monitor our traffic redistribution out of the affected infrastructure, however this is not resolving the impact as we anticipated. We’re reviewing additional logging to develop alternate mitigation options to address the continual service errors.
Components affected
Outlook.com
Latest Updates ( sorted recent to last )
4 days ago - at 10/01/2025 03:25AM

Title: Users may experience errors or failures when accessing their Outlook mailbox through any connection method
User impact: Users may experience errors or failures when accessing their Outlook mailbox through any connection method.
Current status: We're continuing to monitor our traffic redistribution out of the affected infrastructure, however this is not resolving the impact as we anticipated. We’re reviewing additional logging to develop alternate mitigation options to address the continual service errors.
Next update by: Wednesday, October 1, 2025, at 6:00 AM UTC

4 days ago - at 10/01/2025 01:52AM

Title: Potential issues accessing Outlook mailboxes through one or more connection methods
User impact: Users may experience errors or failures when accessing their Outlook mailbox through any connection method.
Current status: We've identified a portion of infrastructure responsible for processing request flow traffic that isn't operating at expected thresholds. We've since redistributed traffic to alternate infrastructure and are monitoring to confirm if our actions alleviate impact as expected.
Next update by: Wednesday, October 1, 2025, at 4:00 AM UTC

4 days ago - at 10/01/2025 01:03AM

Title: Potential issues accessing Outlook mailboxes through one or more connection methods
User impact: Users may experience errors or failures when accessing their Outlook mailbox through any connection method.
We're investigating a potential issue and checking for impact to your organization. We'll provide an update within 60 minutes.
Next update by: Wednesday, October 1, 2025, at 2:00 AM UTC

Be the First to Know When Vendors Go Down

With IsDown, you can monitor all your critical services' official status pages from one centralized dashboard and receive instant alerts the moment an outage is detected. Say goodbye to constantly checking multiple sites for updates and stay ahead of outages with IsDown.

Start free trial

No credit card required · Cancel anytime · 4484 services available

Integrations with Slack Microsoft Teams Google Chat Datadog PagerDuty Zapier Discord Webhook