Writing a codeplug from a newer version of CPS (Customer Programming Software) to an older firmware version.

The radio powers on but stays on the Hytera logo indefinitely.

If the radio is completely unresponsive (no LEDs, no PC detection), the internal bootloader may be damaged. In some advanced repair circles, this requires opening the radio and momentarily shorting specific "boot pins" on the logic board to ground while powering up.

Ensure your computer is not set to go to sleep or turn off USB ports during the transfer. Conclusion

A power failure or cable disconnection during a flash.

The CPS no longer recognizes the radio, even though the cable is plugged in and the drivers are active. How to Fix a Hytera Flashburn

Never flash a portable on a low battery. Always use a fully charged battery or a battery eliminator connected to a stable power supply.