DFU Hijacking

When DFU hijacking occurs, the Betaflight Configurator will not recognize the flight controller that is in DFU mode. At the same time, you will observe the following situation in the computer's device manager

If the situation described above occurs, please try desoldering all peripherals from the flight controller. This will prevent the flight controller from being unable to enter DFU mode and flash the firmware due to DFU hijacking.

When the flight controller enters DFU mode, it searches for inputs from various peripherals, including USB VCP and UART. If an external device (such as a receiver or GPS) is connected to the UART and sends content that appears valid, the bootloader will focus on the UART port and attempt to load firmware from it, preventing entry into DFU mode. Every flight controller typically has a port that is primed for the bootloader, usually either UART1 or UART3

For more detailed information, you can refer to Betaflight's official documentation: Hijacking | Betaflight