https://devzone.nordicsemi.com/f/nordic-q-a/82722/sd-bl-app-dfu-update-failureHi everyone , I want to perform DFU of SD+Bl+APP via UART. I use nrfutil version 6.1.3. The Softdevice is s140_nrf52_7.2.0_softdevice.hex and the application is based on SDK 17.0.2 . I prepared a ZIP file using : The zip contains: 3.0.0en-USTelligent Community 13Tue, 14 Dec 2021 10:06:42 GMThttps://devzone.nordicsemi.com/thread/343352?ContentTypeID=1Tue, 14 Dec 2021 10:06:42 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c754f927-2b1f-43af-8112-f5cd39871997Rafalino<p>Turns out that I didn&#39;t use the correct bootloader.</p> <p>Once I changed to UART bootloader everything started working.</p><div style="clear:both;"></div>