Ez most azért külön hsz., mert hosszú lesz...

Többféle megoldás található a neten, többet ki is próbáltam, nekem ez vált be:

My answer is going to summarize only the difference between the rest of the answers (i.e. Disabling Hyper-V and Device guard) and the following steps :

If you used Group Policy, disable the Group Policy setting that you used to enable Windows Defender Credential Guard (Computer Configuration -> Administrative Templates -> System -> Device Guard -> Turn on Virtualization Based Security).

Delete the following registry settings:

HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\LSA\LsaCfgFlags HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\DeviceGuard\EnableVirtualizationBasedSecurity HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows\DeviceGuard\RequirePlatformSecurityFeatures

Important : If you manually remove these registry settings, make sure to delete them all. If you don't remove them all, the device might go into BitLocker recovery.

Delete the Windows Defender Credential Guard EFI variables by using bcdedit. From an elevated command prompt(start in admin mode), type the following commands:

mountvol X: /s

copy %WINDIR%\System32\SecConfig.efi X:\EFI\Microsoft\Boot\SecConfig.efi /Y

bcdedit /create {0cb3b571-2f2e-4343-a879-d86a476d7215} /d "DebugTool" /application osloader

bcdedit /set {0cb3b571-2f2e-4343-a879-d86a476d7215} path "\EFI\Microsoft\Boot\SecConfig.efi"

bcdedit /set {bootmgr} bootsequence {0cb3b571-2f2e-4343-a879-d86a476d7215}

bcdedit /set {0cb3b571-2f2e-4343-a879-d86a476d7215} loadoptions DISABLE-LSA-ISO

bcdedit /set {0cb3b571-2f2e-4343-a879-d86a476d7215} device partition=X:

mountvol X: /d

Restart the PC.

Accept the prompt to disable Windows Defender Credential Guard.

Alternatively, you can disable the virtualization-based security features to turn off Windows Defender Credential Guard.

Egyébként az RSAT-ot mindig újra kell telepíteni, ha nagy frissítés van, én már a 1803-nál is szívtam ezzel... (főleg, hogy az nem volt kompatibilis az azt megelőzővel )