Users may not see options to select GPT models in Microsoft 365 Copilot

Timeline (UK time)

1. 20 Oct 2026, 06:17 BST ✓ Operational

   Title: Users may not see options to select GPT models in Microsoft 365 Copilot User impact: Users may not have seen options to select GPT models in Copilot. Final status: We've completed the reversion of the previous change and confirmed internally that impact has been successfully resolved. To receive the latest version containing the fix, users will need to restart their Copilot app. Scope of impact: This issue may have affected any user attempting to utilize GPT models in Copilot. Start time: Monday, October 19, 2026, at 7:23 AM UTC End time: Tuesday, October 20, 2026, at 3:41 AM UTC Root cause: A recent change, which was intended to filter out model groups based on policy ID, introduced a configuration issue that resulted in impact. Next steps: - We're reviewing our update procedures to understand why the configuration issue for the policy ID filter for model groups wasn't caught during the testing phase. This will allow us to drive service improvements by proactively identifying similar issues in the future and improve our update testing processes. This is the final update for the event.

2. 19 Oct 2026, 23:53 BST ✓ Operational

   Title: Users may not see options to select GPT models in Microsoft 365 Copilot User impact: Users may not see options to select GPT models in Copilot. Current status: We're monitoring the final step of the change reversion process which will fully revert the previous change back to the last known healthy build to resolve the issue. Scope of impact: This issue may affect any user attempting to utilize GPT models in Copilot. This section may be updated as our investigation continues. Start time: Monday, October 19, 2026, at 7:23 AM UTC Root cause: A recent change, which was intended to filter out model groups based on policy ID, introduced a configuration issue that’s resulting in impact. Next update by: Tuesday, October 20, 2026, at 7:00 AM UTC

3. 19 Oct 2026, 21:48 BST ✓ Operational

   Title: Users may not see options to select GPT models in Microsoft 365 Copilot User impact: Users may not see options to select GPT models in Copilot. Current status: Our change reversion process requires a bit longer than previously expected, and we now expect it to complete by our next scheduled communication update. Scope of impact: This issue may affect any user attempting to utilize GPT models in Copilot. Start time: Monday, October 19, 2026, at 7:23 AM UTC Root cause: A recent change, which was intended to filter out model groups based on policy ID, introduced a configuration issue that’s resulting in impact. Next update by: Tuesday, October 20, 2026, at 12:30 AM UTC

4. 19 Oct 2026, 19:53 BST ✓ Operational

   Title: Users may not see options to select GPT models in Microsoft 365 Copilot User impact: Users may not see options to select GPT models in Copilot. Current status: We're proceeding with our process to revert the change. Based on our current estimations, we anticipate this will be completed by our next scheduled communication update, remediating impact for all users. Scope of impact: This issue may affect any user attempting to utilize GPT models in Copilot. Start time: Monday, October 19, 2026, at 7:23 AM UTC Root cause: A recent change, which was intended to filter out model groups based on policy ID, introduced a configuration issue that’s resulting in impact. Next update by: Monday, October 19, 2026, at 10:30 PM UTC

5. 19 Oct 2026, 19:04 BST ✓ Operational

   Title: Users may not see options to select GPT models in Microsoft 365 Copilot User impact: Users may not see options to select GPT models in Copilot. Current status: We’ve identified a recent change, which intended to filter out model groups based on policy ID, introduced a configuration issue that’s resulting in impact. We’re reviewing options to revert this change to restore access to these impacted models and remediate impact for all users. Scope of impact: This issue may affect any user attempting to utilize GPT models in Copilot. Root cause: A recent change, which was intended to filter out model groups based on policy ID, introduced a configuration issue that’s resulting in impact. Next update by: Monday, October 19, 2026, at 7:30 PM UTC

6. 19 Oct 2026, 18:50 BST ✓ Operational

   Title: We're looking into a potential problem impacting Microsoft 365 Copilot User impact: We're checking for potential impact to your users. Current status: We're investigating a potential issue with Microsoft Copilot 365 and checking for impact to your organization. We'll provide an update within 30 minutes.