https://devzone.nordicsemi.com/f/nordic-q-a/52245/nrf52840-dongle-bootloader-updateHello, I tried to update bootloader on the dongle via DFU, but It failed. The dongle uses OpenBootloader, so it does not check signature for firmware packages. But the OpenBootloader requires bootloader packages to be signed. Is it possible to finden-USTelligent Community 13Tue, 17 Sep 2019 15:22:59 GMThttps://devzone.nordicsemi.com/thread/210188?ContentTypeID=1Tue, 17 Sep 2019 15:22:59 GMT137ad170-7792-4731-bb38-c0d22fbe4515:d3ed2dd6-c075-42a0-86cf-e450733d1c02ilia<p>Thank you</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/210186?ContentTypeID=1Tue, 17 Sep 2019 15:13:26 GMT137ad170-7792-4731-bb38-c0d22fbe4515:1ca19c97-49af-4e5f-a64c-e72fe7b35ac0Sigurd<p>Hi,</p> [quote userid="25033" url="~/f/nordic-q-a/52245/nrf52840-dongle-bootloader-update"]Is it possible to find private key, that used in open bootloader, to sign my bootloader package?[/quote] <p>No.</p> [quote userid="25033" url="~/f/nordic-q-a/52245/nrf52840-dongle-bootloader-update"]Or should I flash my bootloader manually?[/quote] <p>Yes, see <a href="https://devzone.nordicsemi.com/f/nordic-q-a/43874/entering-dfu-mode-switches-port-number/172525#172525">this post</a> for more information.</p><div style="clear:both;"></div>