/FULL_DUPLEX /NOFULL_DUPLEX (default) Enables full-duplex operation of a LAN device. Before full-duplex operation results from the use of this qualifier, additional device or network hardware setup may be required. Some devices may be enabled for full-duplex operation by default. Some devices may not allow the setting to be changed. The /NOFULL_DUPLEX qualifier disables full-duplex operation.