The exception was: java.net.BindException: Address already in use: bind
Perhaps a server is already running on that port?
you can't create to servers on one port...!
you need to change the port of the server in the server.properties file
-> the value you need to change is 'server-port'
I have been reading other forum posts similar to this and one, has narrowed it down to the extracted version of optifine. This has happened to me, and I’m no expert but I think if you play with a different mod until the issue fixes, it will work.