I recently ran into an issue trying to execute a java program on one of our master build servers. Java was complaining that the JVM was having an issue binding to a port, saying that it was in use. A quick scan of the taskmanager revealed that there were a couple of Java processes running but it wasn’t obvious whether they were the culprit. A little bit of Google hunting revealed the use of netstat, however, another commenter on that blog suggested the use of TCPView.
TCPView is essentially taskmanager coupled with netstat. It presents you with all kinds of connection information as well as the process that are using the connections. TCPView also provides process details and the ability to kill processes.