Pixhawk 2.4.8 Usb connection problem

Hi . I have a Pixhawk 2.4.8 . I use it on the Talon FPV(Fixed wing.) When i saw the Firmware Arduplane v4.0.4 , i try to load new firmware .When i try , my usb connect was cut. There is no com port on the MissionPlanner. Its only show " Auto " . When i click it , it cant find my Pixhawk.I did try to connect my pixhawk different computers but i had the same problem.I had format the SD Card but there is no change.Please help me about that problem …

I suggest asking at discuss.ardupilot.org for ArduPilot questions

It solved.
I installed the correct driver than i restarted the pc and it works. My Pixhawk 2.4.8 is connecting to pc very well.