Can you put NM-B in conduit for exterior use?

NM-B (non-metallic sheathed cable) is not approved for use in conduit for exterior applications. It is designed for indoor use in dry locations and should not be exposed to moisture or adverse weather conditions. If you need to run electrical wiring outdoors, you should use a type of cable specifically rated for wet locations, such as UF (underground feeder) cable or use individual conductors in appropriate conduit. Always check local codes and regulations for specific requirements.