This tutorial will teach you how to resolve the error that reads “An authentication error has occurred. The function requested is not supported” while using Windows 10 Remote Desktop Connection feature.
Mostly, this error is reported to witnessed by users when trying to connect to remote computer using Remote Desktop Protocol or RDP in Windows 10. According to some, this issue has popped up only after they updated their Windows.
Methods to Fix RDP “An authenticantion error has occurred. The function requested is not supported” Error
To help you fix this annoying error while using Windows 10 Remote Desktop Connection feature, we will go through multiple methods.
Please note that this tutorial is applicable to Windows 10 only.
Method # 01: Windows Update Fix
If you think that you are getting this issue after you updated your Windows or otherwise, you should follow the simple steps given below:
- Open Windows Run by pressing ‘Windows + R’.
- Type ‘ms-settings:windowsupdate’ and enter.
- If you are using Windows 7 or older, type ‘wuapp’ in Windows Run.
- Now on the newly opened window, click on ‘check for updates’.
Follow the same steps across the others computers which you are connecting to. Make sure to restart the PC’s after downloading and installing updates.
Hopefully this will fix the issue.
Method # 02: Registry Editor:
If method # 01 didn’t work for you, there is still good news as some users had their issue fixed after making changes to the ‘AllowEncryptionOracle’ inside the registry editor. Follow these steps to work it out:
- Press Windows + R to open Windows Run. type ‘regedit’.
- Follow the following path: HKEY_LOCAL_MACHINE/Software/Microsoft/CurrentVersion/Policies/System/CredSSP/Parameters.
- On the right side you should see ‘AllowEncryptionOracle’. Double-click on it.
- Change its Value Data to ‘2’.
- Save the changes and reboot your PC.
If this does not fix the issue, do not worry, we still got one more for you.
Method # 03: Local Group Policy Editor
If you are using Home version of Windows 7, 8.1 or 10. You should skip this step. Or you can work your way around on installing the Local Group Policy Editor for the Windows versions mentioned above.
- Open Windows Run by pressing ‘Windows Key + R’. type ‘gpedit.msc’ and enter.
- Follow this path: Computer Configuration/Administrative Templates/System/Credentials Delegation.
- Now look for ‘Encryption Oracle Remediation’ on the right side of the screen and double click it.
- Make sure it is ‘enabled’. Just below this ‘enabled’ option, you should see ‘protection level’, set it to ‘vulnerable’.
- Make sure to save the changes applied and reboot your PC.
Hopefully, after following the aforementioned steps, you will be able to get rid of an “authentication error has occurred. The function requested Is not supported.” error while using Remote Desktop Connection in Windows 10.