I can't reproduce any error with, can you try this too. ``` #!define MQTT_HOST "test.mosquitto.org" loadmodule "mqtt.so" modparam("mqtt", "host", MQTT_HOST) modparam("mqtt", "port", 8883) modparam("mqtt", "keepalive", 5) #modparam("mqtt", "id", MQTT_NODE_NAME) #modparam("mqtt", "username", MQTT_USER) #modparam("mqtt", "password", MQTT_PASS) modparam("mqtt", "will_topic", "kamailio123") modparam("mqtt", "will", "gone") modparam("mqtt", "verify_certificate", 0) // download crt file from https://test.mosquitto.org/ssl/mosquitto.org.crt modparam("mqtt", "ca_file", "/etc/kamailio/certs/mosquitto.org.crt") ```