https://devzone.nordicsemi.com/f/nordic-q-a/49961/nrf9160-mqtt-nb-connect-lte-failedHi After upgrade modem to mfw_nrf9160_1.0.0. Most of our SIM cards still working good on both AT and MQTT projects. Two of our SIM cards can&#39;t connect to LTE when uses MQTT default project. These two SIM still can connect to LTE when uses AT commanden-USTelligent Community 13Fri, 19 Jul 2019 05:55:49 GMThttps://devzone.nordicsemi.com/thread/199408?ContentTypeID=1Fri, 19 Jul 2019 05:55:49 GMT137ad170-7792-4731-bb38-c0d22fbe4515:bff7ab3a-e589-4c74-aa7d-230c7f9e185eLeoChen<p>Thanks, the CONFIG_LTE_NETWORK_MODE_NBIOT=y is working.</p> <p><span>The AT command setting XSYSTEMMODE in MQTT project also working.</span></p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/199280?ContentTypeID=1Thu, 18 Jul 2019 12:34:36 GMT137ad170-7792-4731-bb38-c0d22fbe4515:68ea386a-8663-4034-8590-78a149b989a4Bj&#248;rn Kvaale<p>What you want to do is either set the XSYSTEMMODE command in the code itself, similar to how the asset tracker does this, or set the following in the prj.conf file for your project:</p> <p>CONFIG_LTE_NETWORK_MODE_NBIOT=y</p> <p>This should automatically set the mqtt example to nB-IoT. You can then check using the Link Monitor to see if the XSYSTEMMODE has been set correctly. Also, make sure to open the project in a new build folder after you save the changes to the prj.conf file. Otherwise, it may not switch to nB mode.</p> <p>Which error do you receive when setting XSYSTEMMODE in MQTT project?</p><div style="clear:both;"></div>