Most likely, the LoggerNet server is not running. If LoggerNet Admin is used, the LoggerNet server can run as a service. If LoggerNet is used, the program needs to be running for the server to be running.
If a user is logging in to a remote LoggerNet server, not only does the LoggerNet server need to be running on the remote machine, but the user must be able to reach the machine through the network and log in to the machine if access is restricted.