This issue can occur when the following prerequisites are met:
Expected behavior: Websites added by users should not be automatically trusted by Symantec Endpoint Protection 12.1 since the Registry value Security_HKLM_only is set to 1.
Actual behavior: Websites added by users can sometimes be automatically trusted by Symantec Endpoint Protection 12.1, even when Security_HKLM_only is set to 1.