DFU thread Server nrfutil ncp connectivity issue

[pawel3cte]

Hi,

I've been trying any way I can think of to work around an issue "51" returned by nrfjprog executed from nrfutil when trying to run serwer from the steps in tutorial:
https://devzone.nordicsemi.com/nordic/short-range-guides/b/mesh-networks/posts/thread-tutorial-practical-guide-for-device-upgrade-ota

It ends up with:

File "subprocess.py", line 512, in run
subprocess.CalledProcessError: Command '['nrfjprog', '--snr', '683191406', '--verify', '/tmp/_MEI0grNYG/nordicsemi/thread/hex/ncp.hex', '--family', 'NRF52']' returned non-zero exit status 51.

I had tried to program ncp.hex from source package of the same nrfutil version and next I tried to use nrfutil without '--flash_connectivity' but then I get:

2020-12-17 09:48:42,784 Failed to reset NCP. Please flash connectivity firmware.

I tried doing it on Linux and Windows machine. I tried different relese( v5.2.0 ). All gives nothing but errors.