https://devzone.nordicsemi.com/f/nordic-q-a/47211/dfu-should-we-update-the-mbr-when-updating-sd-6-0-0-to-6-1-1Hello, I&#39;m currently designing a custom bootloader to perform a DFU. So far I&#39;m able to update the bootloader and the application, however there is a problem when I try to update the softdevice (It is updated by the bootloader, not by the MBR). Ien-USTelligent Community 13Mon, 13 May 2019 13:35:50 GMThttps://devzone.nordicsemi.com/thread/186739?ContentTypeID=1Mon, 13 May 2019 13:35:50 GMT137ad170-7792-4731-bb38-c0d22fbe4515:dd765865-24d1-49cd-9091-12e5aabe7668Tim<p>Hello Vidar, thank you for your answer. No I didn&#39;t remove the MBR section with nrfutil, I don&#39;t use this script, we have our own script that creates files in a proprietary format. But the script basically takes the softdevice image except for addresses 0x0-0x1000.&nbsp;</p> <p>Anyway I&#39;ve found where the issue was and fixed it, the MBR part is correct and it&#39;s good to have your confirmation that this is the good way to update the softdevice.</p> <p></p> <p>Have a nice evening !&nbsp;</p> <p>Tim&nbsp;</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/186716?ContentTypeID=1Mon, 13 May 2019 12:58:54 GMT137ad170-7792-4731-bb38-c0d22fbe4515:6e27e017-4aaa-4b21-b5b5-ba00b9148a0dVidar Berg<p>Hello,</p> <p>No, you have understood it correctly, the MBR shall not be erased during DFU. Did you remember to remove the MBR section from the Softdevice image (nrfutil will do this when you create a Softdevice DFU package)? It&#39;s also important that the Softdevice is not &quot;invoked&quot; through the MBR command when you perform this step.&nbsp;</p><div style="clear:both;"></div>