Microsoft 365 Alert – Service Degradation – Microsoft Copilot (Microsoft 365) – Users may experience degradation with Copilot responses after uploading a file – RESOLVED

Announcements Arpan Das

11/06/2026 09:58:00 AM

NHSmail Reference: INC46848795

Microsoft Reference: CP1386444

Issue Status: RESOLVED

Issue Description: Users may experience degradation with Copilot responses after uploading a file.

More info: Affected users may be returned an error message stating, “Oops! Something happened. Can you try again?”

Users report low-quality responses or hallucinations when Copilot is prompted to respond on content within uploaded files.

Final Update: 12/06/2026 09:03:00 AM – Microsoft has completed the scale-out of our configuration change to prevent retries from adding more load during OneDrive or SharePoint Online file uploads. After a period of monitoring for file upload traffic across affected regions, we’ve confirmed that our actions successfully remediated impact.

Scope of impact: Some users may experience degradation with Copilot responses after uploading a file. This section may be updated as the investigation progresses.

Root cause: Normal growth in Microsoft 365 Copilot usage exceeded the available resources needed to process OneDrive and SharePoint Online file upload requests, causing some requests to process slower or fail.

Next steps : Microsoft are continuing to monitor previously affected traffic to confirm what additional performance optimizations we can implement to further improve the resiliency of our service to prevent similar impact scenarios from occurring in the future.