I get the exception "java.net.SocketException: Address already in use" whenever I try to run rmiregistry. Why?

Govind Seshadri

The exception means that there is already an rmiregistry process running on the default port 1099 on that machine. You can either choose to kill it and restart rmiregistry, or start it up on a different port , say port 9999, as:

rmiregistry 9999