MC1189910 - Configure Local Network Access Policy for Microsoft eCDN

Updated February 19, 2026: We have updated the content. Thank you for your patience. 

We're making some changes to the Microsoft eCDN configuration.

Starting with Chrome 142,146, browsers will enforce Local Network Access restrictions that may impact Microsoft eCDN peer-to-peer functionality.

How this will affect your organization:

You are receiving this message because our reporting indicates one or more users in your organization may be using this Microsoft eCDN. To maintain optimal performance for Teams Live Events and Town Halls, admins must configure the LocalNetworkAccessAllowedForUrlsLocalNetworkAccessAllowedForUrls policy for Chrome-based browsersbrowsers.

What you need to do to prepare:

Admins will need to:

AddFor complete, up-to-date details (including required URLs, deployment methods, and tenant-specific considerations), see the following URLs to the LocalNetworkAccessAllowedForUrls policy in your environment:

• *.ecdn.teams.microsoft.com
• https://teams.microsoft.com
• *.ecdn.teams.cloud.microsoft
• https://teams.cloud.microsoft
• https://engage.cloud.microsoft/

Apply these settings via Group Policy or registry keys for:

• official Microsoft Edge: HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Edge\
• Google Chrome: HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Google\Chrome\

For US Government tenants, use GCC/GCC High-specific hostnames as outlined in the documentation.eCDN documentation: Configure Local Network Access Policy for Microsoft eCDN.

Additional Notes:

• This change aligns with Microsoft’s Unified Domains initiative. Ensure your network filters include both legacy and new domains.
• Pair this configuration with WebRtcLocalIpsAllowedUrls for full peer-to-peer functionality.
• Firefox restrictions are planned but not yet enforced.

See documentation for full guidance: Configure Local Network Access Policy for Microsoft eCDN