https://devzone.nordicsemi.com/f/nordic-q-a/85823/impossible-to-see-device-tty-from-thingy91Hello, I follow up this documentation https://developer.nordicsemi.com/nRF_Connect_SDK/doc/1.9.1/nrf/ug_thingy91_gsg.html#updating-firmware-through-external-debug-probe to update my device. Before I update my device with the last version I coulden-USTelligent Community 13Tue, 15 Mar 2022 13:50:45 GMThttps://devzone.nordicsemi.com/thread/358237?ContentTypeID=1Tue, 15 Mar 2022 13:50:45 GMT137ad170-7792-4731-bb38-c0d22fbe4515:5cd7eea6-9fdb-4d82-968e-427313bb2f0fAmanda Hsieh<p>Hi,</p> <p>Happy to know you fix the issue. You could click &quot;Verify Answer&quot; to close the case.</p> <p>-Amanda</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/358223?ContentTypeID=1Tue, 15 Mar 2022 13:17:18 GMT137ad170-7792-4731-bb38-c0d22fbe4515:fa5f2e95-70ad-4b89-8dcd-b852b5552890Vincent MORENO<p>Ok sorry I understood I was using the bad hex file. I had to use dfu_hex because I use boot system.</p><div style="clear:both;"></div>