https://devzone.nordicsemi.com/f/nordic-q-a/120146/nrf-programmer-app-not-flashing-a-custom-board-even-when-in-bootloader-with-mcuboot-enabled1. Description and how to recreate it Im attempting to flash a custom board with a nrf5340 on board using mcuboot via nrf Programmer v4.5.0. When I put the board in bootloader mode it tells me that No operation possible. I saw a post from abouten-USTelligent Community 13Wed, 26 Mar 2025 05:47:50 GMThttps://devzone.nordicsemi.com/thread/528958?ContentTypeID=1Wed, 26 Mar 2025 05:47:50 GMT137ad170-7792-4731-bb38-c0d22fbe4515:a535fcbb-68a5-49dd-bdf2-193c24071f98papadkostas<p>You can have a look here as well&nbsp;<a id="" href="https://github.com/nrfconnect/sdk-mcumgr">https://github.com/nrfconnect/sdk-mcumgr</a><br />I also lost a bit of time trying to flash with programmer application until I tried AuTerm.<br />I followed the intermediate course and I cannot recall that was mentioned anywhere.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/528910?ContentTypeID=1Tue, 25 Mar 2025 16:56:57 GMT137ad170-7792-4731-bb38-c0d22fbe4515:332796cd-ddf6-4f06-9c37-39568cb6efd5GregFriedholm<p>Sounds good Thank you Vidar&nbsp;</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/528909?ContentTypeID=1Tue, 25 Mar 2025 10:19:50 GMT137ad170-7792-4731-bb38-c0d22fbe4515:1420c138-3b5b-4b08-be7a-55452dd813c3Vidar Berg<p>Hello,</p> <p>The Programmer app does not currently support programming over the mcumgr protocol on custom boards. Instead you can use AuTerm as described in this devacademy course at&nbsp;<a href="https://academy.nordicsemi.com/courses/nrf-connect-sdk-intermediate/lessons/lesson-9-bootloaders-and-dfu-fota/topic/exercise-1-dfu-over-uart/">https://academy.nordicsemi.com/courses/nrf-connect-sdk-intermediate/lessons/lesson-9-bootloaders-and-dfu-fota/topic/exercise-1-dfu-over-uart/</a>.</p> <p>Best regards,</p> <p>Vidar</p><div style="clear:both;"></div>