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Update your firewall rules: Teams and Copilot are changing address

infonewsLLM-Specific

security

Source: CSO OnlineSeptember 11, 2026

Summary

Microsoft is redirecting Microsoft 365 and Teams web users to new addresses (copilot.cloud.microsoft and teams.cloud.microsoft) starting this month. Organizations need to update their firewall rules (network security settings that control which addresses devices can connect to) and other network configurations to maintain access to these services before the early October deadline.

Solution / Mitigation

Organizations should review and update configurations on client devices, proxies, firewalls, secure web gateways, or other enterprise network controls to allow connections to the new addresses. For enterprises that blocked the Copilot address to prevent personal account access, Microsoft recommends using its TenantRestrictions control instead. Companies unable to meet the early October deadline should contact their Microsoft account representative for help.