Microsoft Admin Center

Title: Some users in the United States and United Kingdom may be unable to access Microsoft 365 services User impact: Users in the United States and United Kingdom may be unable to access Microsoft 365 services. More info: Impacted users may encounter 502 or 503 errors when attempting to access Microsoft 365 services. Current status: Our investigation remains focused on the cause of the Single Sign-On (SSO) failures and associated 5xx errors. In parallel, we're reviewing upstream dependencies to determine whether they are contributing to the impact. While some affected customers have reported improvement in service availability, our investigation continues as we work towards a full resolution. Start time: Wednesday, September 16, 2026, at 1:22 PM UTC Next update by: Wednesday, September 16, 2026, at 4:30 PM UTC