Microsoft Investigates Outage Affecting Teams and Office for the Web
Severity: Medium (Score: 48.9)
Sources: Bleepingcomputer, Feeds.4Sysops, Cybersecuritynews
Published: · Updated:
Keywords: microsoft, teams, office, investigates, service, outage, investigating
Severity indicators: service outage, outage
Summary
Microsoft is investigating a significant service outage impacting users of Teams and Office for the web, preventing access to files. Affected applications include Excel and PowerPoint, with users receiving error messages indicating that online services are unavailable. The company is analyzing service telemetry to identify the root cause of the issue. This incident follows a recent cache configuration change that caused high CPU and memory utilization, affecting multi-factor authentication setup for some accounts. Microsoft has not disclosed specific regions affected or a timeline for resolution. The situation is ongoing, and further updates are expected as the investigation continues. Key Points: • Microsoft is investigating a service outage affecting Teams and Office for the web. • Users are unable to access files, encountering error messages about service unavailability. • The outage is linked to a recent cache configuration change impacting system performance.
Detailed Analysis
**Impact** Users of Microsoft Teams and Office for the web, including Excel and PowerPoint, are unable to open files, encountering error messages indicating service unavailability. The outage affects multiple Office Apps and has a noticeable user impact but lacks specific geographic or sector details. The incident disrupts collaboration and productivity for cloud-based users, potentially impacting business operations reliant on these services. No data breach or data at risk has been reported. **Technical Details** The root cause is under investigation, with initial analysis suggesting a cross-service issue impacting Office for the web experiences. A recent cache configuration change requiring a failover triggered high CPU and memory utilization during peak traffic from European Union customers, contributing to platform access issues. No evidence of malware, CVEs exploited, or attacker TTPs has been disclosed. No IOCs are available. **Recommended Response** Defenders should monitor Microsoft 365 service health dashboards and official communications for updates on remediation and restoration. Review and adjust cache configurations and failover mechanisms if applicable within their own environments. No specific patches or detection rules have been identified; maintaining vigilance on service telemetry and user reports is advised until the incident is resolved.
Source articles (3)
- Microsoft investigates Office Apps, Teams file access issues — Bleepingcomputer · 2026-06-01
Microsoft says an ongoing incident is preventing users of its Teams collaboration platform and Office for the web cloud-based productivity suite from opening files. "We're investigating reports that s… - Microsoft Office for the Web and Teams Hit by File Access Outage — Cybersecuritynews · 2026-06-01
Microsoft experienced a service disruption affecting users’ ability to open files through Office for the Web and Microsoft Teams, with the company confirming resolution after investigating elevated er… - Microsoft investigates service outage affecting Office for the web and Teams — Feeds.4Sysops · 2026-06-01
Microsoft is currently investigating a widespread service incident that prevents users from accessing files through cloud-based productivity tools. The outage specifically impacts Microsoft Teams and…
Timeline
- 2026-06-01 — Microsoft announces service outage: Microsoft reported a widespread service incident affecting Teams and Office for the web, preventing file access for users.
- 2026-06-01 — Error messages reported by users: Affected users are receiving messages stating that online services are unavailable while Microsoft investigates.
- Recent — Previous incident linked to cache configuration change: A recent cache configuration change caused high CPU and memory utilization, impacting multi-factor authentication setup.
Related entities
- Microsoft (Company)