Please download the latest release package:
https://github.com/openmv/openmv/releases/download/v1.4/firmware.zip
Extract the package, and use the IDE’s bootloader to upload this file:
openmv_v1.4/firmware/OPENMV2/openmv.bin file.
When the camera starts/restarts the bootloader runs for about 500 milliseconds (you’ll see the Green LED blinking quickly), after that it jumps to the main app, Blue LED starts blinking, you should wait for the Blue LED to blink before connecting.
Let us know how it goes.