Use the official Baofeng CPS to read your radio and save your codeplug (channels, contacts). OpenGD77 uses a different codeplug format, but you can export your channels as CSV.
Try running the software as an administrator, or check for a loose connection. baofeng dm1702 firmware update
: If the COM port doesn't appear, reinstall the Prolific or CH340 USB-to-Serial drivers. Use the official Baofeng CPS to read your
Remove the battery and look at the PCB (Printed Circuit Board) inside the battery compartment. If you see a large chip labeled "STM32F405," you have a V2. If you see a "BK4819" or unlabeled main processor, proceed with extreme caution—stick to official Baofeng updates only. baofeng dm1702 firmware update
What is the of the firmware you want to install? Does your DM-1702 model include built-in GPS ?