Visual Studio Unable to Login Despite Whitelisted URLs and Port 443 Open

Hi @Agus Umriadi ,

Thank you for sharing your concern to us.

Regarding your question:

1. Please make sure that these endpoints are all in whitelisted, as they are required for Visual Studio sign in steps: *.msftauth.net *.live.com visualstudio.microsoft.com app.vsspsext.visualstudio.com app.vssps.visualstudio.com api.vstsusers.visualstudio.com go.microsoft.com graph.windows.net graph.microsoft.com login.microsoftonline.com management.core.windows.net management.azure.com api.subscriptions.visualstudio.microsoft.com
2. To avoid any unexpected block, you can follow these steps:

3.

• Maintain updated lists of required authentication endpoints from the vendor (Microsoft publishes these for Azure AD and Office 365).
  • Exclude authentication traffic from SSL inspection where possible.
  • Test conditional access policies in audit mode before enforcing them broadly.
  • Monitor logs for blocked connections to confirm whether firewall/proxy rules are interfering.

4. If you want to check, you can follow these steps:
   • Download "[Fiddler 4 Classic]" app and install it on the machine where you can reproduce the problem. This is a third-party program, but it's recommended by Microsoft.
   • Enable HTTPs decryption: Tools -> Options -> Https -> select ‘decrypt HTTPS Traffic’ (you may be prompted to install the Fiddler certificate – make sure to select Yes)
   • Close your app that is experiencing the issue. We want to see the end-2-end flow of the app and how it interacts with Microsoft services.
   • Disable caching: Rules -> Performance -> Disable Caching
   • Make sure Fiddler is turned on to capture traffic
   • Launch the Visual Studio app.
   • Try again to sign in and you should see https traffic showing up in the Fiddler window.

If my answer is helpful, I will appreciate if you can provide me some feedback to let me know. Otherwise, feel free to let me know if you still have any questions or concern related.

Have a nice day!

To troubleshoot the login issue with Visual Studio, consider the following points:

1. Additional URLs/Endpoints: Ensure that the following endpoints are also whitelisted, as they are commonly required for Visual Studio authentication:
   • *.liveshare.vsengsaas.visualstudio.com
   • *.azure.com
   • *.microsoft.com
2. WebView/Embedded Browser: Visual Studio does use an embedded browser for authentication. This means that any restrictions on web views or embedded browsers could potentially block the login process. Ensure that your firewall or security settings do not interfere with this.
3. Known Issues: There can be various issues related to proxy settings, SSL inspection, and firewall filtering that might affect authentication. If you are using a proxy, ensure that the http_proxy and https_proxy environment variables are set correctly. Additionally, check if SSL inspection is causing issues by bypassing it for Microsoft URLs.
4. Diagnostic Logs: You can enable diagnostic logging in Visual Studio to better understand what might be blocking the authentication. Look for logs related to authentication or network connectivity, which can provide insights into any blocked endpoints.

For further assistance, consider reaching out to Microsoft support or checking the Visual Studio community for similar issues and solutions.

References:

• Troubleshoot sign in issues
• Debugging proxy errors