B4J Question Address Already in use : JVM_Bind...?

I think we would need more information to diagnose this. You put this in the B4J forum but you mentioned B4A-Bridge. Are you connecting to the PI. If so I would check firewall for blocks. Also can you ping the IP of the PI.

Actually the OP mentioned B4J-Bridge not B4A-Bridge.

Is it possible that B4J-Bridge is already running?
Try to kill all java.exe processes.