Microsoft 365 Alert – Service Degradation – SharePoint Online – Some users may be unable to access SharePoint Online sites configured with Authentication Context – ONGOING

Announcements Sharmista Mohanta

01/09/2026 09:00:00 AM

NHS.net Connect Reference: INC46923176

Microsoft Reference: SP1464785

Issue Status: ONGOING

Issue Description: Users may be unable to access SharePoint Online sites configured with Authentication Context.

More info: Specifically, users are unable to access SharePoint Online sites configured with Authentication Context through sensitivity labels.

Users receive the following error message:
“Server Error in ‘/’ Application.”

As a workaround, users may be able to temporarily access the affected content by first clearing internet browser cookies and navigating to the root site collection before opening the direct link. Users can also open a new browser tab on the same session and access the site. The link may work as well.

Current Update: 03/09/2026 09:20:00 AM – The deployment is progressing as expected and users will see relief as it progresses. They expect the release to complete, mitigating impact for all users by the next scheduled update.

Scope of impact: Some users attempting to access SharePoint Online sites configured with Authentication Context through sensitivity labels may be impacted. This information may be updated as the investigation continues.

Root cause: A recent SharePoint Online code change intended to update authentication processing resulted in Authentication Context requests not being processed as expected, preventing some users from accessing affected sites.

Next update by: Friday, September 4, 2026, at 7:00 PM UTC