If DigiCert G2 certificates are not trusted, authentication failures will occur when accessing Microsoft Entra services. o Impacted domains include:  login.microsoftonline.com  login.live.com  login.windows.net  autologon.microsoftazuread-sso.com 

Hello Kumar, Naveen (external),

It looks like you're dealing with issues related to DigiCert G2 certificates not being trusted during authentication with Microsoft Entra services. Here’s what you can do to check and resolve the issues outlined in your question:

Trust All Root and Subordinate CAs:

• You can check the trusted CAs in your local or organization’s certificate store. Make sure that all the Root and Subordinate CAs mentioned in the Azure Certificate Authority documentation are listed and trusted.

Ensure Trust for “DigiCert Global Root G2”:

  - Verify that the “DigiCert Global Root G2” and its subordinate CAs are indeed trusted. This can usually be done in the certificate management console (e.g., `certmgr.msc` on Windows).
  
  **Remove Client-Side Pinning**:
  
     - For any applications or services that implement certificate pinning to the DigiCert Global Root CA, consider removing this pinning. Check the application documentation for instructions on disabling or adjusting the pinning settings.
     
     **Update Your Settings**:
     
        - Make sure to update your network infrastructure and applications now to avoid any service disruption, especially if you have not yet done so.
        

If you're uncertain about any specific steps or need further guidance, here are a few follow-up questions to clarify your situation:

1. What specific errors are you encountering related to the DigiCert G2 certificates?
2. Are these trust issues occurring on all devices or specific ones within your network?
3. What operating system and version are you using?
4. Have you already checked the certificate store for the presence and trust status of the required certificates?
5. Are there any applications that specifically rely on these certificates, and what are they?

Hope this helps you get things sorted out! For more detailed steps, check out these resources:

• Troubleshoot issues with Microsoft Entra authentication
• Certificate-Based Authentication issues
• Configure Microsoft Entra authentication for your SQL Server VM

Feel free to reach out if you need more help!