"Some users may experience intermittent sign‑in failures, including 'too many requests' errors or unexpected sign‑outs," Microsoft said in a recent update on the company's service health status page.
Microsoft service health status update
Microsoft has acknowledged an ongoing Outlook.com outage that is producing intermittent sign‑in failures and automatic sign‑outs for customers. In its public service health update the company wrote: "Our investigation indicates client sign‑in scenarios may be contributing to the reported behaviour, and we're focused on validating interactions across service components to identify next steps." Microsoft has not yet disclosed a root cause, nor has it provided figures for how many users or which regions are affected.
User reports and Downdetector
The problem has been visible in third‑party outage monitoring. Downdetector received "thousands of user reports" after the incident began, which the company said has been ongoing for more than three hours. Most of those reports, according to the record, describe login failures and connection issues rather than complete loss of the service.
Scope and severity: labelled "service degradation"
Microsoft has flagged the incident as causing "service degradation," a designation the company uses for problems that have noticeable user impact but do not render the service completely unavailable to everyone. The live symptoms reported by Microsoft and users are mainly unexpected sign‑outs and "too many requests" errors during sign‑in attempts, consistent with intermittent failures rather than an all‑out outage.
Related outages reported last month
The company pointed to recent, separate disruptions that required mitigation. Last month Microsoft mitigated an Exchange Online outage that blocked access to mailboxes and calendars via Outlook on the web, Outlook desktop, Exchange ActiveSync, and other Exchange Online connection protocols. On the same day it addressed a different issue that caused Office.com or Microsoft 365 Copilot web sign‑in problems, affecting the Microsoft Copilot desktop app, Copilot in Microsoft Teams, and Copilot in Office apps.
What this means for technologists, enterprises, and end users
- Technologists and security teams: Microsoft’s update highlights client sign‑in scenarios as a possible contributor, so teams responsible for identity and access should be watching the service health status page and validating client interactions with Outlook.com and related components.
- Affected enterprises and procurement leaders: The "service degradation" label and Microsoft’s prior month incidents underline the potential for intermittent disruption across multiple access methods; procurement and continuity planners will likely track recovery timelines and cross‑check alternative access paths for critical mail and calendar functionality.
- End users: Individuals attempting to reach mailboxes may encounter sign‑outs and "too many requests" errors; affected customers should expect intermittent failures until Microsoft completes its validation across service components.
This remains a developing incident: Microsoft is actively investigating client sign‑in interactions, has signalled ongoing validation across service components, and has not released a cause, scope, or regional breakdown. Users and organizations reliant on Outlook.com should monitor Microsoft’s service health page for updates while Microsoft works to identify next steps.
