Provide the Windows version of both client and server, and whether this is a workgroup or domain environment.

Bypass potential DNS or hostname resolution issues by entering the remote computer's directly into the Remote Desktop Connection client instead of its name. 3. Adjust Firewall Rules

: If you are using a VPN, disconnect and reconnect. Slow or high-latency VPN connections are a primary cause of this specific error code. Detailed Troubleshooting Guide 1. Fix Expired RDP Certificates (Server Side)