Live status of all services Advisory · resolved

Users may be seeing unexpected users when changing accounts in Microsoft 365 Copilot Chat

Microsoft 365 Copilot Chat CW1523046

Users may have seen unexpected users when changing accounts in Microsoft 365 Copilot Chat.

Status
Service restored
Feature
General
Region
Not specified (all regions)
Started
Oct 5, 2026, 13:23 CEST
Resolved
Oct 24, 2026, 00:30 CEST
Duration
18 days 11 h

More info

While we work to improve the long-term stability of our code change, users won't be able to use the "change account" feature.

Affected users were unable to modify or access these unexpected users in any way.

Scope of impact

Users attempting to change account in Microsoft 365 Copilot Chat may have seen unexpected users.

Root cause

A recently deployed build of Microsoft 365 Copilot Chat contained an issue that showed unexpected users when changing accounts in Microsoft 365 Copilot Chat.

Next steps:
- We're improving the "change account" feature to ensure that its functionality aligns with user expectations.

This is the final update for the event.

Final status

We've determined that our best option to ensure a comprehensive resolution is to temporarily disable the "change account feature" while we prepare a code change to ensure that this feature is only available for the expected scenarios. After we finalize our code improvements, we'll re-enable this feature.

Timeline

Every update Microsoft posted for this issue, newest first.

  1. Oct 24, 2026, 01:19 CEST

    We've determined that our best option to ensure a comprehensive resolution is to temporarily disable the "change account feature" while we prepare a code change to ensure that this feature is only available for the expected scenarios. After we finalize our code improvements, we'll re-enable this feature.

  2. Oct 24, 2026, 00:15 CEST

    We've reviewed recent changes to Microsoft 365 Copilot Chat and identified an update that correlates with the time this issue began. We're considering our options to revert it back to a healthy build to remediate impact.

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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.