Teams and Copilot are changing addresses: update your firewalls

Microsoft is updating the destination addresses for two of its most widely used services - Microsoft 365 and Teams - requiring organizations to adjust their firewalls and network configurations accordingly. Starting this month, users will see redirects to copilot.cloud.microsoft for Teams and teams.cloud.microsoft for Microsoft 365 web users. The company made this announcement in two MessageCenter posts (MC1465764 and MC1462915) and advised enterprises to update systems and documentation to maintain access.

Microsoft has urged customers to review configurations on client devices, proxies, firewalls, secure web gateways, and other enterprise network controls to ensure continual connectivity to these new addresses. Companies experiencing difficulties connecting should verify their environment adheres to the recommended network requirements for Microsoft 365 Copilot.

Those struggling may use Microsoft’s TenantRestrictions control to continue blocking the new Copilot address while still allowing access to personal Microsoft accounts.

Microsoft aims to complete all necessary redirects by early October, but requests for extensions can be made by contacting the account representative if the deadline cannot be met. Limited exceptions to the Teams redirect will be granted until December 31, 2026, after which no further delays will be permitted.