The "handshake" requires the device to be in a specific state at the exact microsecond the software looks for it. The Battery Pull:
Your computer does not have the correct USB drivers for your phone’s chipset (e.g., MediaTek USB VCOM drivers). Result: The phone may appear as "Unknown Device" or "MTK USB Port" without a proper COM port number assigned. it cannot find the meta usb com port for modem handshake
Open or Tera Term on that COM port (e.g., COM5): The "handshake" requires the device to be in