The KVL 4000 hangs on the "Please wait" continuously when attempting to load Radio Authentication keys to APX radios, and the keys are never loaded to the radio.  To recover the KVL 4000, the KVL must be power cycled.

The KVL 4000 shows "Please wait" on the screen and never loads the Radio Authentication keys to the radio. 

The APX radio is connected to the KVL 4000 using the USB cable.  The radio is properly configured to the correct System and WACN ID as the KVL.  Both the KVL and radio are properly configured for communication.

The appropriate product Serial Cable and DB9 Gender Changer must be used for Radio Authentication key loading.