https://devzone.nordicsemi.com/f/nordic-q-a/32758/sd-bl-otau-form-sd132-ver-3-1-0-to-sd112-ver-5-1-0Hi, During SD+BL OTAU form SD132 ver 3.1.0 to SD112 ver 5.1.0, Old bootloader copied new one using function nrf_dfu_mbr_copy_bl(uint32_t * p_src, uint32_t len); to bad address 0x79888 instead of 0x74000 proper BL address. How to do OTAU from SD132en-USTelligent Community 13Tue, 27 Mar 2018 07:19:54 GMThttps://devzone.nordicsemi.com/thread/126058?ContentTypeID=1Tue, 27 Mar 2018 07:19:54 GMT137ad170-7792-4731-bb38-c0d22fbe4515:0032362d-4a7f-4f6c-b635-eca40fbb6f77chris222<p>I solve problem by using module nrf_dfu_util.c from new SDK (<span>SD112 ver 5.1.0</span>) to compile&nbsp;BL SD132</p><div style="clear:both;"></div>