: High packet loss, poor VPN throughput, or slow Internet Service Provider (ISP) routing can cause the security negotiation phase to time out.
I’ve been using RDP for years, but hitting was a new level of vague troubleshooting. The connection fails immediately during the “Securing remote connection” phase. No helpful message from Microsoft—just these codes. : High packet loss, poor VPN throughput, or
The fastest fix is usually Solution 1 . By disabling the NLA requirement, you force the connection to authenticate at the session layer rather than the network layer, bypassing the specific handshake causing error 0x904 . No helpful message from Microsoft—just these codes
: Expired or missing self-signed certificates on the host machine are a frequent cause. certlm.msc , navigate to Remote Desktop > Certificates , and check for expired entries. Delete expired certificates and restart Remote Desktop Services ) to force Windows to generate a new one. Configure Firewall Exceptions Remote Desktop (WebSocket) : Expired or missing self-signed certificates on the
Try these solutions in order. Each step solves a specific subset of error code 0x904 scenarios.