So this question asks whether its possible to revert/undo settings previously configured by Group Policy. As explained in the great answer, because of "tattooing", the change will be made and there is no way to know or revert to anything else.
However, I don't need to revert, I need to go back to defaults. In some cases, GPOs will do exactly that when using "Disabled" or "Not configured" but in other cases, such as in the Windows Settings\Security Settings area, you "define" or "not define". Define "tattoos" a setting, and enforces it. Not defining it, simply removes the enforcement.
How can you revert security settings back to defaults? Can you simply delete the related registry key as a one-time task GPP? Is that at all recommended for something as important as security policies?
Context: I've inherited a terrible mess of Group Policies. Some of which are pushing horribly insecure security policies that I wish to simply remove and allow Windows to default, rather than enforce a new setting.
HEMAN85's link mentions this in it's list, but for simplicity and succinctness:
secedit /configure /cfg %windir%\inf\defltbase.inf /db defltbase.sdb /verboseThe templates it's restoring SHOULDN'T have been messed with... unless whomever set everything up did something super wonky. Also note this is just for security, but that's what I think you were asking.
I really don't know your purposes, but here is a few ways to do it: http://www.thewindowsclub.com/reset-all-group-policy-settings-to-default