Users in the United Kingdom may experience errors or failures when accessing their mailboxes in Exchange Online.

Title: Users in the United Kingdom may experience errors or failures when accessing their mailboxes in Exchange Online. User impact: Users may experience errors or failures when accessing their mailbox via one or more Exchange Online connection methods. Final status: We've confirmed through service health telemetry that availability has recovered, and that the impact to mailbox access in Exchange Online has been resolved. Start time: Friday, July 24, 2026, at 11:00 PM UTC End time: Saturday, July 25, 2026, at 12:58 AM UTC Root cause: This issue may have impacted users in the United Kingdom who attempted to access their mailboxes. Next steps: - We're continuing to monitor service health telemetry to ensure that the traffic remains balanced in an effort to avoid impact like this in the future. This is the final update for the event.

Title: Potential issues accessing mailboxes via one or more connection methods User impact: Users may experience errors or failures when accessing their mailbox via one or more Exchange Online connection methods. Current status: We're investigating a potential issue and checking for impact to your organization. We'll provide an update within 60 minutes.