What will you do when you encounter the error “An authentication error has occurred”? If you don’t know, then this post written by MiniTool is what you need. You can find several efficient methods to fix the error.
When you try to establish a connection with another remote computer using Remote Desktop Connection, you may get an error message saying that “An authentication error has occurred the function requested is not supported”.
So how to fix the “Remote Desktop An authentication error has occurred” error? The methods are shown below.
Method 1: Change the Remote Desktop Settings
In order to fix the “An authentication error has occurred the function requested is not supported” error, the first step you can take is to change the remote desktop settings.
Here is the tutorial:
Step 1: Press the Win key + R key at the same time to open the Run box.
Step 2: Type sysdm.cpl in the box and then click OK to open the System Properties window.
Step 3: Go to the Remote tab and then uncheck the Allow connections only from computers running Remote Desktop with Network Level Authentication (recommended) option. Click Apply and OK to save changes.
Step 4: Restart your computer and then check if the “An authentication error has occurred” error is gone.
Method 2: Change the Group Policy Settings
You can also try to change the Group Policy settings to fix the “An authentication error has occurred” error. Follow the detailed instructions below:
Step 1: Open the Run box and then type gpedit.msc in the box. Click OK to open the Local Group Policy Editor window.
Step 2: Click Computer Configuration and then select Administrative Templates > System > Credentials Delegation on the left of the window.
Step 3: Double-click the Encryption Oracle Remediation on the right of the window.
Step 4: Choose Enabled and then select the Vulnerable option under the Protection Level drop-down menu. Click Apply and OK to save changes.
Step 5: Close all the windows. Type cmd in the Run box and then click OK to open the Command Prompt window.
Step 6: Type gpupdate /force in the window and then press Enter.
Step 7: Reboot your computer and then check if the error is fixed.
Method 3: Edit the Registry
There is another method you can try to fix the “An authentication error has occurred” error – edit the Registry. Here is a quick guide:
Step 1: Type regedit in the Run box and then click OK to open the Registry Editor window.
Step 2: Navigate to HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Policies\System\CredSSP\Parameters.
Step 3: Double-click the AllowEncryptionOracle DWORD to open its Edit DWORD window.
Step 4: Change the Value data to 2 and then click OK.
Step 5: Reboot your computer and then check if the “An authentication error has occurred” error is fixed.
Bottom Line
There are three useful methods to fix the “An authentication error has occurred” error in this post: change the remote desktop settings, change the Group Policy settings and edit the Registry.