Hi, I've had success with this product if both PCs are on the same network, but when attempting a link via internet on 2 different networks it does not work.
USB over Network works via the Internet as well as via the local network. All that you need to connect two PCs (for all cases) is the DIRECT IP address of the Server (PC where device is connected physically). When two PCs are on different networks, they have only their local IP addresses, so in this case you need to configure port forwarding on Server PC. You can also create VPN connection between these two PCs.