Allow connections to copilot.cloud.microsoft before the Copilot URL redirect

🚨 The Signal: Microsoft Copilot web app will redirect from m365.cloud.microsoft to copilot.cloud.microsoft in September 2026. Organizations must update network and security controls to allow the new domain to prevent service disruption.

The Impact

Network and security teams are affected; unaddressed, this poses a risk of Copilot service unavailability.

  • Network teams: Must update firewall and proxy rules for the new Copilot domain.
  • Security teams: Need to review and adjust security gateway policies for Copilot access.
  • End-users: May experience Copilot outages if network changes are not implemented.
  • IT administrators: Will troubleshoot access issues if network controls are not updated.

The Action

  1. Identify all network devices (firewalls, proxies, security gateways) that filter outbound traffic.
  2. Review existing rules for m365.cloud.microsoft and determine if they need modification or duplication.
  3. Add copilot.cloud.microsoft to allowed domains/URLs on all relevant network and security controls.
  4. Test connectivity to copilot.cloud.microsoft from various network segments before September 2026.
  5. Document the changes for audit and compliance purposes.

Domain: Agentic-AI · Impact: high · Workload: Other