https://devzone.nordicsemi.com/f/nordic-q-a/41725/ble-advertising-does-not-consistently-startHi, I have been running into a problem where I am getting inconsistently failure to start advertising. Calling: err_code = ble_advertising_start(&amp;m_advertising, BLE_ADV_MODE_FAST ); returns NRF_SUCCESS, but the advertising process does not starten-USTelligent Community 13Thu, 03 Jan 2019 02:12:24 GMThttps://devzone.nordicsemi.com/thread/163617?ContentTypeID=1Thu, 03 Jan 2019 02:12:24 GMT137ad170-7792-4731-bb38-c0d22fbe4515:c4288b02-6692-4775-98ed-17117677dda2scao<p>Figured out the problem.<br /><br />When flash is in use when turning on advertising,&nbsp;</p> <pre>p_advertising-&gt;<span>advertising_start_pending</span></pre> <p><span>is set true, and NRF_SUCCESS returned.<br /><br />But&nbsp;</span></p> <pre>ble_advertising_on_sys_evt(<span>uint32_t </span>evt_id, <span>void </span>* p_context)</pre> <p>is needed to actually process this flag and turn on BLE advertising later. Problem was it wasnt added as a softdevice observer, so the flag was never processed.</p> <p><br /><br /><br /></p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/162795?ContentTypeID=1Fri, 21 Dec 2018 09:03:26 GMT137ad170-7792-4731-bb38-c0d22fbe4515:3f634e57-ec49-4d8a-aa56-f79c11939063Hakon<p>Are you using an example from the sdk? What device are you using? Is it a Nordic dk or a custom board?</p><div style="clear:both;"></div>