The snmptd probe installed on a Linux server is not processing any traps. A tcpdump shows that the traps are arriving. There are no firewall rules blocking the port and "netstat -anp" does not show the snmptd process binding to port 162. In this environment, the snmptd process is owned by a non-root user.
Either change the port that the snmp traps are sent out on and configure the snmptd probe to retrieve them from that port, or change the UIM ownership to root.