Pyro4 Python "socket.error: [Errno 101] Network unreachable"

Question

I have a strange error in a Python / Pyro4 application, I use two Microsoft Windows machines, one with Windows 7, and the other with 8.1, connected via Ethernet; first, I register both Pyro objects on the name server, one using the Root tag in the name server and the other with the Handler tag, the application first acquires the proxy Root object and uses it without problems, but when it's time to call the method, contained in the Handler object, it gives

socket.error: [Errno 101] Network is unreachable problem...

I run each component (Pyro object) in a separate thread, any help evaluates what happens here as soon as I can post some code.