Microsoft 365 Alert – Service Degradation – Microsoft Copilot (Microsoft 365) – Users may be unable to view SharePoint Online files that are linked by Copilot Chat or Copilot agents – RESOLVED

Announcements Arpan Das

30/06/2026 09:57:00 AM

NHSmail Reference: INC46865041

Microsoft Reference: CP1409288

Issue Status: RESOLVED

Issue Description: Users may be unable to view SharePoint Online files that are linked by Copilot Chat or Copilot agents.

More info: When users select the link to a SharePoint Online file that has been provided by Copilot Chat or Copilot agents, they receive an error that says, “We couldn’t show the file.”

The issue may also impact links to Microsoft Word, Microsoft Excel, Microsoft PowerPoint, and PDF files.

Final Update: 08/07/2026 08:55:00 AM –Microsoft has completed deployment of our long-term fix, and they confirmed with a subset of affected users that the functionality was restored and that clicking the links opened the SharePoint Online files in the same window as expected.

Scope of impact: This issue may potentially impact any user attempting to view SharePoint Online files that are linked by Copilot Chat or Copilot agents.

Root cause: A recent change intended to improve the file preview experience for Copilot Chat is causing errors when attempting to open linked files.

Next steps : Microsoft is reviewing our service change testing and validation procedures to identify and prevent similar issues when deploying changes to the file preview experience moving forward.