Navigate to .
If you can connect to some servers but not others on the same network, an expired certificate is the most likely culprit. Navigate to
The is a generic network-related failure that prevents a client from establishing a session with a remote host. While it is often caused by unstable network conditions, it can also stem from expired security certificates, firewall blocks, or specific Windows 11 compatibility issues. Common Causes of Error 0x904 valid self-signed certificate.
Windows Defender or third-party antivirus software (like Bitdefender) blocking mstsc.exe or RDP traffic. Navigate to
Search for in the Start menu. Click Change settings .
Windows will automatically generate a new, valid self-signed certificate.