[Fixed] The Server Security Layer Detected An Error (0x80090304) in the Protocol Stream

The server security layer detected an error (0x80090304) in the protocol stream and the client has been disconnected

“I tried to connect to my work PC via RDP from home but failed. My work PC has this event log appearing when I tried to connect from my home PC: ‘The server security layer detected an error (0x80090304) in the protocol stream and the client (Client IP: XXX) has been disconnected.’ Both computers are Windows 7. How can I fix this?”

Three solutions to “The server security layer detected an error (0x80090304) in the protocol stream” on Windows 7

To help you fix “The server security layer detected an error (0x80090304) in the protocol stream and the client has been disconnected” on Windows 7, we introduce three solutions in this part.

Solution 1. Disable NLA on the server side

Step 1. Press Win + R to invoke the Run dialog box. Then type in “sysdm.cpl” and hit OK to open System Properties.

Step 2. Go to the Remote tab and uncheck Allow connections only from computers running Remote Desktop with Network Level Authentication (recommended) to disable NLA.

Solution 2. Remove the certificate and re-create a new one on the client computer

Step 1. Press Win + S to open the Search box, type in Credential Manager, and then open it.

Step 2. Switch to Windows Credentials. Find the credential you want to delete and then click Remove.

Step 3. Then click Add a Windows credential.

Step 4. You would see a dialog in which you have to enter the domain, network or website address, username, and password. Click on OK to add the credential.

Solution 3. Check the RDP Protocol Version on the client computer

Step 1. Hold down the Windows key and press R to bring up the Run prompt. Type in “mstsc” then click OK.

Step 2. Right-click in the title bar and select About.

Step 3. The bottom line of the text will read Remote Desktop Protocol #.# supported. If this is less than 8.0 you’ll need to upgrade.

Step 4. My Remote Desktop Protocol is less than 8.0, so I need to download and install DTLS (KB2574819).

Step 5. Download and install RDP 8.0 (KB2592687).

Step 6. Restart the computer.

Free & easy RDP alternative: AnyViewer

If you happen to encounter “The server security layer detected an error (0x80090304) in the protocol stream and the client (Client IP: XXX) has been disconnected”, you can try the solutions to troubleshoot. Here we also want to offer you another option, which is to use a free RDP alternative AnyViewer. It is easy to operate. You can achieve unattended remote access with only a few steps.

Step 1. Download, install and launch AnyViewer on both computers.

Step 2. Go to Log in, and then click Sign up. (If you already have signed up on its official website, you can log in directly.)

Step 3. Fill in the signup information.

Step 4. Then you can see you successfully logged in to AnyViewer. Your device will automatically be assigned to the account you've logged in to.

Step 5. Log in to the same AnyViewer account on the two devices, then click One-click control to achieve unattended remote access.

Conclusion

This post mainly introduces three ways to troubleshoot “The server security layer detected an error (0x80090304) in the protocol stream and the client (Client IP: XXX) has been disconnected.” if you happen to encounter this error, you can refer to this post. Besides, we have also introduced a backup option for you. You can use AnyViewer if you would like to try an easy and convenient remote desktop tool.