Execute os dois comandos a seguir no prompt Executar:
REG add "HKCU\Software\Policies\Microsoft\Windows\System" /v DisableCMD /t REG_DWORD /d 0 /f
REG add "HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System" /t Reg_dword /v DisableRegistryTools /f /d 0