Windows Defender or third-party antivirus software (like Bitdefender) blocking mstsc.exe or RDP traffic.
The self-signed certificate used by Remote Desktop Services has expired and failed to renew automatically.
Click , browse to C:\Windows\System32\mstsc.exe , and add it to the list. 4. Adjust Security Layers (NLA Issues) browse to C:\Windows\System32\mstsc.exe
Windows will automatically generate a new, valid self-signed certificate.
If you can connect to some servers but not others on the same network, an expired certificate is the most likely culprit. high packet loss
Insufficient bandwidth, high packet loss, or a sluggish VPN connection.
Check the expiration date of the certificate. If it is expired, right-click and it. browse to C:\Windows\System32\mstsc.exe
Disable . Troubleshooting Checklist Unable to RDP into some Windows Servers - Error code: 0x904