-102 error when flashing nRF52840 Dev Kit via J-Link Plus

I get an error and the flashing fails when I attempt to flash the nRF52840 DK via an external J-Link Plus connected to the Debug In connector (P18).

Programming of the nRF52840 DK using the J-Link Onboard (OB) device in the Interface MCU (via USB port J2) works with no issues.

Programming a different board containing a nRF54H20 using the same external J-Link Plus and the same installed tool chain works with no issues.

The error which is reported is:

-- west flash: using runner nrfjprog
-- runners.nrfjprog: reset after flashing requested
-- runners.nrfjprog: Flashing file: C:\Work\Attune\GitHub\git2\gen2_firmware\headset\build_dk\merged.hex
[error] [ Client] - Encountered error -102: Command read_device_info executed for 140 milliseconds with result -102
[error] [ Worker] - An unknown error.
[error] [ Client] - Encountered error -102: Command read_memory_descriptors executed for 31 milliseconds with result -102
Failed to read device memories.
[error] [ Worker] - An unknown error.
ERROR: JLinkARM DLL reported an error. Try again. If error condition
ERROR: persists, run the same command again with argument --log, contact Nordic
ERROR: Semiconductor and provide the generated log.log file to them.
NOTE: For additional output, try running again with logging enabled (--log).
NOTE: Any generated log error messages will be displayed.
FATAL ERROR: command exited with status 33: nrfjprog --program 'C:\Work\Attune\GitHub\git2\gen2_firmware\headset\build_dk\merged.hex' --sectoranduicrerase --verify -f NRF52 --snr 602009303

From reviewing other issues I found the suggestion to try "nrfjprog --recover" but that also failed with a similar error "-102":

[error] [ Client] - Encountered error -102: Command connect_to_emu_with_snr executed for 186 milliseconds with result -102
ERROR: Unable to connect to a debugger.
[error] [ Worker] - An unknown error.
ERROR: JLinkARM DLL reported an error. Try again. If error condition
ERROR: persists, run the same command again with argument --log, contact Nordic
ERROR: Semiconductor and provide the generated log.log file to them.
NOTE: For additional output, try running again with logging enabled (--log).
NOTE: Any generated log error messages will be displayed.

I tried updating the J-Link software & driver to see if that would help, but it did not.

So, I followed the suggestion to run with --log and that log,log file is attached here:

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[2025-Mar-08 14:14:29] [debug] --------------------------------------------------------------------------------
[2025-Mar-08 14:14:29] [debug] C:\Program Files\Nordic Semiconductor\nrf-command-line-tools\bin\nrfjprog.exe --log --recover
[2025-Mar-08 14:14:29] [debug] nrfjprog version 10.24.2 external
[2025-Mar-08 14:14:29] [debug] --------------------------------------------------------------------------------
[2025-Mar-08 14:14:29] [ info] Load library at C:\Program Files\Nordic Semiconductor\nrf-command-line-tools\bin\nrfjprog.dll.
[2025-Mar-08 14:14:29] [ info] Library loaded, loading member functions.
[2025-Mar-08 14:14:29] [ info] Member functions succesfully loaded.
[2025-Mar-08 14:14:29] [debug] [ Client] - open
[2025-Mar-08 14:14:29] [debug] [ Client] - start
[2025-Mar-08 14:14:29] [ info] [ Client] - stdout: Jlinkarm nRF Worker ready. Handling sequence 004a8bbe-8af9-4fba-b623-9469ea2dc5f8.
[2025-Mar-08 14:14:29] [debug] [SeggerBackend] - Logger sink registered in Segger backend logger
[2025-Mar-08 14:14:29] [trace] [ Client] - Command open executed for 36 milliseconds with result 0
[2025-Mar-08 14:14:29] [debug] [ JLink] - Logger sink registered in JLink logger
[2025-Mar-08 14:14:29] [debug] [ nRFXX] - open
[2025-Mar-08 14:14:29] [debug] [ nRFXX] - just_check_family
[2025-Mar-08 14:14:29] [debug] [SeggerBackend] - open_dll
[2025-Mar-08 14:14:29] [debug] [SeggerBackend] - No J-Link DLL path was provided. Attempting to auto detect.
[2025-Mar-08 14:14:29] [ info] [SeggerBackend] - Load library at C:\Program Files\SEGGER\JLink_V818\JLink_x64.dll.
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