Occasionally computers may have multiple network interface card. If all cards are functional and are connected to the network that doesn't create problems for YAPI.
When one or more cards are not connected to the network you should disable those cards using Windows Manage Network Connections screen. Note that you will need administrative privileges for performing this action.
In case you can't disable network card, find the network card that is connected to the network and record its MAC address. Create a text file mymac.txt in YAPI folder. Enter network card's MAC address. Restart YAPI