if your theme not changed or its like classic windows you need to install uxtheme patcher from here and after restart select new theme from personalization. Note: Please unistall old or other version of skin packs before install new one. 100% of the details have been worked out.
Best work on 100% scale and layout size, you need to set it from display setting, Also for enable start menu and taskbar skin you need to install startisback from