SAME Boards, SAME CONDITION, SAME PROBLEM. Another Try using another method
What did I Try as the second method:
A. Copied the Bootloader from the Working Board using ULINK Pro into a Hex File.
- Created a uVision Project with the K20DX128Vxx5.
- The following screens show the settings:

Used Save Command as follows to Read the Bootloader into a Hex FIle
SAVE MyFile.hex 0X0, 0X0001FFFF
The hex file was created successfully in the project folder.
B. Flashed the Bricked boards with the copied Hex File.
- Generate a uVision project
- Select ULINKpro as debug interface
- Entered the hex file name into 'Name of Executable' in the dialog 'Options for Target - Output'
- Performed a Flash download.
It showed that the programme has been flashed successfully, but
Same Problem Flashing Successful but the Boards not Working
WHAT NEXT?