Both pc's need their own IP addresses. Have you trie running this troubleshooter?
Sometimes this works..
Shut down both computers; Unplug the router; disconnect the desktop's ethernet cable if connected this way; Plug in router; Boot computers.
Surface Pro (2017) vs Surface Pro 4
20 groundbreaking 3D animation technologies coming to Siggraph 2017
iPad Pro 12.9 vs Surface Pro 5