Hi Simon Haines,
The bootloader on FRDMK64F is the opensda v2.0 reversion.
After download the firmware, it can be the CMSIS DAP or JLINK debugger, it is not the P&E opensda debugger.
So, you can't download the P&E firmware to it.
The firmware can be download from these link:
1. CMSIS DAP (mbed)
Firmware FRDM K64F - Handbook | mbed
After you enter the bootloader mode, send 0226_k20dx128_k64f_0x5000.bin to your "BOOTLOADER", then power off and power on the board again.
2. JLINK firmware
SEGGER - The Embedded Experts - Downloads
After you enter the bootloader mode, send 02_OpenSDA_FRDM-K64F.bin to your "BOOTLOADER", then power off and power on the board again.
If you want to run it in the WIN10, I suggest you use the JLINK firmware, this firmware support WIN10.
Wish it helps you!
Have a great day,
Kerry
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