Before running LabView 8.6 Two "Call Library Function" configurations need updating: In DppApi.vi change the function prototype FROM: DppApi.dll:OpenUSBDevice (frame 2) TO: DppApi.dll:OpenUSBDeviceEx The parameters are correct but the function name is not. Change DppApi.dll:GetUSBDppDeviceInfo (frame 4) calling convention to stdcall(WINAPI). The DppApi.dll function calling convention is stdcall for all functions.