If your environment uses an (common in corporate networks), error 0x904 usually signals that the Gateway is rejecting the connection request due to a policy mismatch. This is the most common cause of 0x904 during automated deployments or installs.
Did the 0x904 error appear immediately after a Windows Update, or has the server been unreachable for an extended period? Fix Remote Desktop Error Code 0x904: 4 Working Solutions 10 Dec 2025 —
When the Microsoft Terminal Services Client ( mstsc.exe ) initializes, it establishes a TCP connection (typically over port 3389) and instantly attempts to negotiate a secure Transport Layer Security (TLS) tunnel. If this handshake drops or gets rejected, the system throws error 0x904. i remote desktop connection error code 0x904 install
Before diving into the fix, it is helpful to know what causes it:
Clear all stored Remote Desktop credentials, as outdated or corrupted credentials can cause the 0x904 error: If your environment uses an (common in corporate
Use PowerShell to verify the RDP port (3389) is actually reachable: Test-NetConnection [ServerIP] -Port 3389 5. Disable Network Level Authentication (NLA) for Testing
Add C:\Windows\System32\mstsc.exe to the allowed list on both the client and host. Fix Remote Desktop Error Code 0x904: 4 Working
Security software blocking Port 3389.
If your environment uses an (common in corporate networks), error 0x904 usually signals that the Gateway is rejecting the connection request due to a policy mismatch. This is the most common cause of 0x904 during automated deployments or installs.
Did the 0x904 error appear immediately after a Windows Update, or has the server been unreachable for an extended period? Fix Remote Desktop Error Code 0x904: 4 Working Solutions 10 Dec 2025 —
When the Microsoft Terminal Services Client ( mstsc.exe ) initializes, it establishes a TCP connection (typically over port 3389) and instantly attempts to negotiate a secure Transport Layer Security (TLS) tunnel. If this handshake drops or gets rejected, the system throws error 0x904.
Before diving into the fix, it is helpful to know what causes it:
Clear all stored Remote Desktop credentials, as outdated or corrupted credentials can cause the 0x904 error:
Use PowerShell to verify the RDP port (3389) is actually reachable: Test-NetConnection [ServerIP] -Port 3389 5. Disable Network Level Authentication (NLA) for Testing
Add C:\Windows\System32\mstsc.exe to the allowed list on both the client and host.
Security software blocking Port 3389.