after I upgrade the firmware (_GNX_USB_Controller_v2_11_7.vkb) from my GNX SEM module with GNX USB Controller, the module does not work anymore. No LEDs are working, nothing happens

I unplugged the USB cable and plug it in again (a short flashing of the blued LED is seen), I switched off my Computer, and restart it... Nothing! Any hints?
Kind regards.