https://devzone.nordicsemi.com/f/nordic-q-a/49389/serialization-of-52840-dk-not-start-uphi all , i run Serialization application between nRF52840-DK ,it not start up. how to Debugging this issue? i have been reset connectivity board,the error message halt ,but the ble device no work(i can&#39;t scan it) UART (BLE) nRF5_SDK_15.3.0_59ac345en-USTelligent Community 13Mon, 08 Jul 2019 08:03:43 GMThttps://devzone.nordicsemi.com/thread/197014?ContentTypeID=1Mon, 08 Jul 2019 08:03:43 GMT137ad170-7792-4731-bb38-c0d22fbe4515:dec31ca0-8942-4553-b26e-17cdf72de1b5Bj&#248;rn Kvaale<p>Have you set up the boards correctly like shown in <a href="https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.sdk5.v15.3.0/nrf51_setups_serialization.html?cp=5_1_1_4">the documentation</a>? Maybe <a href="https://devzone.nordicsemi.com/f/nordic-q-a/17528/serialization-sd_ble_enable-return-nrf_error_invalid_state">this answer</a>&nbsp;is&nbsp;able to help you.</p><div style="clear:both;"></div>