https://devzone.nordicsemi.com/f/nordic-q-a/66498/interface-mcu-on-nrf52840-dk-seems-to-be-deadHi, without any obvious reason one of our nRF52840 DKs stopped being visible over the USB (J2) interface. The nRF52840 is still functional and can be programmed from another DK over the &quot;Debug in&quot; port. Switches on the faulty board are set correctlyen-USTelligent Community 13Tue, 29 Sep 2020 14:00:11 GMThttps://devzone.nordicsemi.com/thread/272090?ContentTypeID=1Tue, 29 Sep 2020 14:00:11 GMT137ad170-7792-4731-bb38-c0d22fbe4515:9959ae10-6785-43df-a379-e324dc12a24bNewtoM<p>Thank you Jared, step 4 from your link worked and we could revive the board.<br />Big thanx!</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/272081?ContentTypeID=1Tue, 29 Sep 2020 13:37:32 GMT137ad170-7792-4731-bb38-c0d22fbe4515:509c00bf-9f94-4913-8b59-a910734c3027Jared<p>Hi,</p> <p>Have you modified anything on the board itself, cut/shorted any solder bridges etc? Could you try re-programming the interface chip by following the step 4 <a href="https://devzone.nordicsemi.com/f/nordic-q-a/24592/my-nrf52-nrf51-dk-kit-doesn-t-work">here</a>. Also, please try the other steps if that one doesn&#39;t help. What is the different switches configured to on the board?&nbsp;</p> <p>regards</p> <p>Jared</p><div style="clear:both;"></div>