https://devzone.nordicsemi.com/f/nordic-q-a/14679/dfu-status-when-bluetooth-disconnectHi, Hardware:PAC10040 Platform: nRF5_SDK_11.0.0_89a8197 Master Control Panel: V4.1.3 1.If dfu has started and transported some data, then disconnect bluetooth and kill app. 2.The second time to connect start dfu, will return DFU_STATUS_INVALID_STATEen-USTelligent Community 13Mon, 27 Jun 2016 10:49:26 GMThttps://devzone.nordicsemi.com/thread/56029?ContentTypeID=1Mon, 27 Jun 2016 10:49:26 GMT137ad170-7792-4731-bb38-c0d22fbe4515:762fb320-0495-4a48-904c-a084d710839eAleksander Nowakowski<p>Nor Android or iOS DFU libraries support resuming using the &#39;report number of stored bytes&#39; op code. I assumed that DFU will erase everything on Start DFU command instead of reporting an invalid state. If that&#39;s the case, I could look into it.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/56028?ContentTypeID=1Thu, 23 Jun 2016 14:10:02 GMT137ad170-7792-4731-bb38-c0d22fbe4515:15897c89-1559-4e81-8ab9-1fe41a277f39FormerMember<p>The reason for this behavior, that the second time connect returns DFU_STATUS_INVALID state is most likely that &quot;continue where the application left&quot; doesn&#39;t work with the current version of the bootloader..</p><div style="clear:both;"></div>