Hello,
Quick Assist communicates over port 443 (https) and connects to the Remote Assistance Service at https://remoteassistance.support.services.microsoft.com
by using the Remote Desktop Protocol (RDP). Use Quick Assist to help users - Windows Client Management | Microsoft Learn
We can find and modify the group policy named "Allow log on through Remote Desktop Services" from Computer Configuration\Policies\Windows Settings\Security Settings\Local Policies\User Rights Assignment
in your Active Directory domain to include only the security group(s) of users authorized to provide remote assistance.
Or create inbound and outbound firewall rule on all domain computers to allow Quick Assist traffic (TCP port 443) only from the internal network or specific IP ranges corresponding to your company's network.
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