Hello @Nasir ,
Thanks for reaching out.
Are you referring to Hybrid Azure AD join? if so then devices to have access to the following Microsoft resources from inside your organization's network:
https://enterpriseregistration.windows.net
https://login.microsoftonline.com
https://device.login.microsoftonline.com
https://autologon.microsoftazuread-sso.com (If you use or plan to use seamless SSO)
If your organization requires access to the internet via an outbound proxy, you can use implementing Web Proxy Auto-Discovery (WPAD) to enable Windows 10 computers for device registration with Azure AD. To address issues configuring and managing WPAD, see Troubleshooting Automatic Detection. In Windows 10 devices prior to 1709 update, WPAD is the only available option to configure a proxy to work with Hybrid Azure AD join.
If you don't use WPAD, you can configure WinHTTP proxy settings on your computer beginning with Windows 10 1709. For more information, see WinHTTP Proxy Settings deployed by GPO or manually by running following cmdlet which import Proxy setting from user context to System netsh winhttp import proxy source=ie
Note:
If you configure proxy settings on your computer by using WinHTTP settings, any computers that can't connect to the configured proxy will fail to connect to the internet.
If your organization requires access to the internet via an authenticated outbound proxy, make sure that your Windows 10 computers can successfully authenticate to the outbound proxy. Because Windows 10 computers run device registration by using machine context, configure outbound proxy authentication by using machine context. Follow up with your outbound proxy provider on the configuration requirements.
Verify the device can access the above Microsoft resources under the system account by using the Test Device Registration Connectivity script.
Look at proxy section from this prerequisites for more information.
Hope this helps.
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