The title of your post asks one question...
...but the body of your post asks another question.
While I realize that they are related, I don't guarantee that mimicking the settings below will enable autoruns.. nor would I suggest that you enable that dangerous feature.
If no polices have been defined for the current user, then this is what you should see by default:
(e.g. no Explorer key under the Policies key)
The local machine policy area has this without any group policy settings being set/changed:
If this computer is a work computer of a member of a domain, then you should check with IT services and/or domain admins before making any changes.
