Solution to the error "An authentication error occurred and the required function is not supported" when connecting to a remote desktop

Try this first:

1. "Win+R" and enter "regedit" to open the registry.
2. 找到\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System
3. Right-click on System and create a new item "CredSSP"
4. Right-click on CredSSP and create a new item "Parameters"
5. Right-click on Parameters to create a new DWORD (32) bit value (D), select hexadecimal (H) as the base, and the file name is AllowEncryptionOracle
6. Double-click AllowEncryptionOracle and set the value to 2
7. OK, you can connect normally.

If unsuccessful, continue trying this method:

1. "Win+R" and enter "gpedit.msc" to bring up the "Local Group Policy Editor".
2. Find "Administrative Templates-System-Credential Assignment-Encrypted Database Modification" in "Local Group Policy Editor" and select Open.
3. Configure this item to "Enabled" and select "Vulnerable" in the protection level below.
4. OK。

PS: [Solution to the unavailability of gpedit.msc]:

• Create a new gpedit.bat file

@echo off

pushd "%~dp0"

dir /b %systemroot%\Windows\servicing\Packages\Microsoft-Windows-GroupPolicy-ClientExtensions-Package~3*.mum >gp.txt

dir /b %systemroot%\servicing\Packages\Microsoft-Windows-GroupPolicy-ClientTools-Package~3*.mum >>gp.txt

for /f %%i in ('findstr /i . gp.txt 2^>nul') do dism /online /norestart /add-package:"%systemroot%\servicing\Packages\%%i"

pause

• Run the system file as an administrator and it can be used normally after the execution is completed.