https://devzone.nordicsemi.com/f/nordic-q-a/29318/nrf51-dk---need-to-press-reset-button-to-relaunch-ble-advert-and-failsHello, Today I&#39;ve a strange behavior of nRF51 DK (everything was working ok until today, the last things I did was to reset the J-link FW after a total erase of the board). Now, when I upload the Softdevice (S130) and after my Application then Ien-USTelligent Community 13Fri, 12 Jan 2018 18:50:30 GMThttps://devzone.nordicsemi.com/thread/116653?ContentTypeID=1Fri, 12 Jan 2018 18:50:30 GMT137ad170-7792-4731-bb38-c0d22fbe4515:032c67f5-69fc-48d0-b247-63338d5d052fJohnM<p>Trying to give you my example, I&#39;ve found the issue: I had my PC Windows 10 Bluetooth running at the same time as my mobile phone Android!</p> <p>That&#39;s why it was painful, erratic and pressing RESET on nRF51 DK board would somewhat solve it (I&#39;m guessing). The Windows Bluetooth was trying to connect any time (via J-Link) conflicting with my mobile phone Android.</p> <p><strong>So the rule is to turn off the Bluetooth device on the platform we are developing on .</strong></p> <p><img src="https://devzone.nordicsemi.com/cfs-file/__key/communityserver-discussions-components-files/4/WindowsBlue.jpg" alt="image description" /></p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/116652?ContentTypeID=1Fri, 12 Jan 2018 11:58:31 GMT137ad170-7792-4731-bb38-c0d22fbe4515:fd1bbb57-369b-4856-a7fa-dace6eac723fBj&#248;rn Kvaale<p>Are you using an SDK example or your own custom application? I&#39;m guessing you didn&#39;t have to press the RESET button before to see your application in nrf Connect Android when everything was working, right? Would you mind uploading your code so I can test it here and see if I get the same error?</p><div style="clear:both;"></div>