https://devzone.nordicsemi.com/f/nordic-q-a/13287/the-dfu-failed-when-dfu-to-99I use SDK9.0,SD8.0,the device is 51822AC,the device can enter to Bootloader mode. As it shows below. Then I selected the .zip file to start DFU But when it reached to 99%,the sequence happened. The system still run the old code. So I checken-USTelligent Community 13Tue, 19 Apr 2016 06:44:25 GMThttps://devzone.nordicsemi.com/thread/50655?ContentTypeID=1Tue, 19 Apr 2016 06:44:25 GMT137ad170-7792-4731-bb38-c0d22fbe4515:15e2d4d2-4307-4e1f-8155-d4763031eea3bjorn-spockeli<p>Glad to hear that you were able to resolve the issue!</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/50656?ContentTypeID=1Tue, 19 Apr 2016 01:24:42 GMT137ad170-7792-4731-bb38-c0d22fbe4515:99abf620-0128-4706-a291-a0fd95e446acMilk<p>Hi Bjørn Spockeli, I have solved this problem ,the reason is that my computer has been installed the Encrypt system.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/50654?ContentTypeID=1Mon, 18 Apr 2016 13:58:15 GMT137ad170-7792-4731-bb38-c0d22fbe4515:55bbb2d8-fe10-4819-b576-5644a9e6c495bjorn-spockeli<p>How do you know that its the old bootloader that is running and not the new one? I would check the return code of <code>dfu_image_validate()</code> in <code>dfu_transport_ble.c</code>. In this function <code>dfu_init_postvalidate()</code> is called and the bootloader will not be updated if this returns an error.</p><div style="clear:both;"></div>