Since, in remote mode the server is started elsewhere, then you know that if they type in the wrong IP address, the server will still be up and running.
So you option of clearing out the GUI and letting them reenter is the best GUI choice.
Now Exception handling in the application as a whole should be kept simple. Meaning you don't have to catch every minute Exception that could happen, but catch the more important ones, especially the ones that the methods are throwing.
and at the bottom of the list catch the more general Exception.
Mark