Live status of all services Incident · resolved

Users may be unable to access Cowork in the Microsoft Copilot 365 User Interface (UI)

Microsoft Copilot (Microsoft 365) CP1540142

Users may have been unable to access Cowork in Copilot UI.

Status
Service restored
Feature
General
Region
Not specified (all regions)
Started
Nov 5, 2026, 17:30 CET
Resolved
Nov 5, 2026, 22:20 CET
Duration
4 h 50 min

More info

When attempting to access Cowork, users may have been redirected to Copilot Chat instead.

Scope of impact

This issue may have affected any user attempting to access Cowork.

Root cause

A recent deployment introduced an issue where additional calls were delivered to multiple API endpoints, which caused our automated traffic management mechanisms to reduce request traffic flow which resulted in impact.

Next steps:
- To help prevent similar impact in the future, we're further reviewing our deployment testing and validation processes and the scenarios which trigger our traffic management automations.

We'll provide a preliminary Post-Incident Report within two business days and a final Post-Incident Report within five business days.

Final status

We've confirmed the service has returned to healthy levels following our deployment to turn off the automated traffic management mechanisms, and we've confirmed with some previously impacted customers that impact is resolved.

Timeline

Every update Microsoft posted for this issue, newest first.

  1. Nov 5, 2026, 23:05 CET

    We've confirmed the service has returned to healthy levels following our deployment to turn off the automated traffic management mechanisms, and we've confirmed with some previously impacted customers that impact is resolved.

  2. Nov 5, 2026, 22:41 CET

    We've completed our deployment to turn off the automated traffic management mechanisms that were reducing request traffic flow and we're reaching out to impacted customers to confirm remediation.

    This quick update is designed to give the latest information on this issue.

  3. Nov 5, 2026, 22:03 CET

    We're working on turning off the automated traffic management mechanisms that are reducing request traffic flow, which we anticipate will resolve impact. We'll aim to provide an estimated time to mitigation in our next scheduled update.

    This quick update is designed to give the latest information on this issue.

  4. Nov 5, 2026, 21:21 CET

    We've completed the roll back of the affecting change. However, we've received reports that impact persists. We believe that additional time is likely needed for our roll back to take effect and for stored cache to update for users to see relief. We're continuing to monitor while we investigate any potential additional actions that may be needed if impact does not remediate as expected.

  5. Nov 5, 2026, 19:57 CET

    We've identified a recent deployment introduced an issue where additional calls are being delivered to multiple API endpoints, which caused our automated traffic management mechanisms to take action to reduce request traffic flow which resulted in impact. We're developing a fix to roll back this change to remediate impact for all users.

  6. Nov 5, 2026, 19:25 CET

    We're investigating a potential issue with Copilot and checking for impact to your organization. We'll provide an update within 30 minutes.

When Microsoft 365 goes down

The live overview shows the current state of every Microsoft 365 service, refreshed every minute from Microsoft Graph.

Live status of all services Subscribe to incidents in LEXOJ

To see whether your own tenant is affected, check Service health in the Microsoft 365 admin center. Only a backup outside Microsoft protects against data loss, and only a tested break-glass account against locked-out admins. We set up both in fixed-scope sprints.

Source: Microsoft Graph, Service Communications API. This is the view of a Swiss Microsoft 365 tenant: services not licensed there are missing, and individual issues may affect your tenant differently. Microsoft names the region only in the issue text. The Switzerland view shows issues for Switzerland, for Europe in general and those without a region, but not issues that only name other countries such as Germany or the UK. This page is not provided by Microsoft.