Sneaker's info was great: I used it to repeatedly run the netstat and compare PID info in Task Manager. What I found, though, was on our Windows2008 R2 server, I had to stop the server's SNMP Trap, and then restart the SolarWinds Trap Service, rather than have them both running.. If I run the server's SNMP Trap service, it takes over and SolarWinds NPM does not get to receive any traps. It was not working at all, though, with the normal start-up process:
SolarWinds Trap Service was Started (automatically), and the server's SNMP Trap was stopped, but i had to get them both started, then stop the server's trap, then restart the SolarWinds Trap service, for SW to grab control of the trap. Before I did all that, I had no netstat process on UDP :162.
Now, there is a PID value for UDP:162 that matches the Task Manager's Services name of SolarWindsTrapService.
I did not even try snmpv3 trap.