The local GPO does have software restriction policies being applied, that's what the Software\Policies\Microsoft\Windows\Safer\CodeIdentifiers\ registry keys point to, and specifically the rule for Software\Policies\Microsoft\Windows\Safer\CodeIdentifiers\TransparentEnabled set to 1 means that Software Restriction Policies are enabled and functional from policy. So, you need to look just a little harder at the local group policies, because your statement before means you missed something obvious: If you need help figuring out how to turn this off, try looking at this technet article. It's in there, and gpresult says so.