If you need to reset policies on a Windows 10 machine, back to the defaults you can do the following from an elevated command prompt:

To reset the Local Policies:

C:\Windows\system32>setedit /configure /cfg C:\Windows\Inf\defltbase.inf /db C:\Windows\defltbase.sdb

Reset Group Policies by removing the following directories. This file remove the directories with prompting to remove the directory tree as well:

C:\Windows\system32>rmdir /S /Q c:\windows\system32\GroupPolicyUsers
C:\Windows\system32>rmdir /S /Q c:\windows\system32\GroupPolicy