detecting network devices

I am running a copy of Dude on my “master” computer (configured to act as a router/NAT device - it runs windows :frowning: ). It is not detecting some devices on my local network for some reason. The computers in question are running Win XP. Since I am running a DHCP server, what is the best way to figure out why these devices aren’t being detected? I read somewhere I should install a local dns.

you can ping your undiscoverable devices? are there firewall? in discovery options is “add serviceless” is checked?